Urbit Developers
  • Hoon

    • Overview
    • Cheat Sheet
    • Irregular forms
    • Hoon Errors
    • Hoon Style Guide
    • Basic Types
    • Advanced Types
    • Auras
    • Standard Library

      • 1a: Basic Arithmetic
      • 1b: Tree Addressing
      • 1c: Molds and Mold-Builders
      • 2a: Unit Logic
      • 2b: List Logic
      • 2c: Bit Arithmetic
      • 2d: Bit Logic
      • 2e: Insecure Hashing
      • 2f: Noun Ordering
      • 2g: Unsigned Powers
      • 2h: Set Logic
      • 2i: Map Logic
      • 2j: Jar and Jug Logic
      • 2k: Queue Logic
      • 2l: Container from Container
      • 2m: Container from Noun
      • 2n: Functional Hacks
      • 2o: Normalizing Containers
      • 2p: Serialization
      • 2q: Molds and Mold-Builders
      • 3a: Modular and Signed Ints
      • 3b: Floating Point
      • 3c: Urbit Time
      • 3d: SHA Hash Family
      • 3e: AES encryption (Removed)
      • 3f: Scrambling
      • 3g: Molds and Mold-Builders
      • 4a: Exotic Bases
      • 4b: Text Processing
      • 4c: Tank Printer
      • 4d: Parsing (Tracing)
      • 4e: Parsing (Combinators)
      • 4f: Parsing (Rule-Builders)
      • 4g: Parsing (Outside Caller)
      • 4h: Parsing (ASCII Glyphs)
      • 4i: Parsing (Useful Idioms)
      • 4j: Parsing (Bases and Base Digits)
      • 4k: Atom Printing
      • 4l: Atom Parsing
      • 4m: Formatting Functions
      • 4n: Virtualization
      • 4o: Molds
      • 5a: Compiler Utilities
      • 5b: Macro Expansion
      • 5c: Compiler Backend & Prettyprinter
      • 5d: Parser
      • 5e: Molds and mold builders
      • 5f: Profiling support
      • Runes

        • Atoms and strings
        • Nock . ('dot')
        • Wild ! ('zap')
        • Change Subject = ('tis')
        • Conditionals ? ('wut')
        • Cores | ('bar')
        • Arms + ('lus')
        • Cells : ('col')
        • Calls % ('cen')
        • Casts ^ ('ket')
        • Structures $ ('buc')
        • Make ; ('mic')
        • Hints ~ ('sig')
        • Imports / ('fas')
        • Terminators -- and ==
        • Limbs and wings

          • Limbs
          • Wings
          • Zuse

            • Table of Contents
            • 2d(1-5): To JSON, Wains
            • 2d(6): From JSON
            • 2d(7): From JSON (unit)
            • 2e(2-3): Print & Parse JSON
          • Arvo

            • Overview
            • Ames

              • Overview
              • Cryptography
              • API Reference
              • Scry Reference
              • Data Types
              • Behn

                • Overview
                • API Reference
                • Scry Reference
                • Examples
                • Clay

                  • Overview
                  • Architecture
                  • Using Clay
                  • Data Types
                  • Scry Reference
                  • API Reference
                  • Examples
                  • Marks

                    • Overview
                    • Writing Marks
                    • Using Marks
                    • Examples
                  • Dill

                    • Overview
                    • API Reference
                    • Scry Reference
                    • Data Types
                    • Eyre

                      • Overview
                      • External API Reference
                      • Internal API Reference
                      • Scry Reference
                      • Data Types
                      • Guide
                      • Gall

                        • Overview
                        • API Reference
                        • Data Types
                        • Threads Reference
                        • Iris

                          • Overview
                          • API Reference
                          • Data Types
                          • Example
                          • Jael

                            • Overview
                            • API Reference
                            • Scry Reference
                            • Data Types
                            • Examples
                            • Threads

                              • Overview
                              • HTTP API
                              • Reference
                              • Gall

                                • Start Thread
                                • Take Result
                                • Take Facts
                                • Stop Thread
                                • Poke Thread
                                • Examples

                                  • Fetch JSON
                                  • Child Thread
                                  • Main-loop
                                  • Poke Agent
                                  • Scry
                                  • Take Fact
                                • Concepts

                                  • Scries
                                  • Subscriptions
                                  • Tutorials

                                    • Move Trace
                                    • Reference

                                      • Cryptography
                                      • Filesystem Hierarchy
                                    • Nock

                                      • Nock Definition
                                      • Explanation
                                      • Example
                                      • Implementations
                                      • Vere

                                        • C Runtime System
                                        • Land of Nouns
                                        • API overview by prefix
                                        • C in Urbit
                                        • Writing Jets
                                        • Cryptography
                                        • Azimuth

                                          • Overview
                                          • Urbit HD Wallet
                                          • Azimuth Data Flow
                                          • Azimuth.eth
                                          • Ecliptic.eth
                                          • Advanced Azimuth Tools
                                          • Life and Rift
                                          • Layer 2

                                            • Layer 2 Overview
                                            • Layer 2 Actions
                                            • Transaction Format
                                            • Rollers
                                            • Roller HTTP RPC-API
                                            • Custom Roller Tutorial
                                          • Glossary

                                            • Ames
                                            • Aqua
                                            • Arm
                                            • Arvo
                                            • Atom
                                            • Azimuth
                                            • Battery
                                            • Behn
                                            • Bridge
                                            • Censures
                                            • chat
                                            • Claims
                                            • Clay
                                            • Comet
                                            • Core
                                            • Delegated Sending
                                            • Desk
                                            • Dill
                                            • Document Proposal
                                            • Dojo
                                            • Door
                                            • Ecliptic
                                            • Event Log
                                            • Eyre
                                            • Galaxy
                                            • Gall
                                            • Gate
                                            • HD Wallet
                                            • Hoon
                                            • Invite Tree
                                            • Iris
                                            • Jael
                                            • Keyfile
                                            • Khan
                                            • Landscape
                                            • Mark
                                            • Moon
                                            • Nock
                                            • Noun
                                            • OTA Updates
                                            • Payload
                                            • pH
                                            • Pier
                                            • Pill
                                            • Planet
                                            • Proxies
                                            • Replay
                                            • Factory Reset
                                            • Naive rollups
                                            • Sail/Udon
                                            • Senate
                                            • Ship
                                            • ship.arvo.network
                                            • Star
                                            • |sync
                                            • Trap
                                            • Upgrade Proposal
                                            • Vane
                                            • Vere
                                            • Voting
                                            • Wallet-Generator
                                            • Additional

                                              • Cryptography
                                              • Software Distribution

                                                • Overview
                                                • Docket File
                                                • Glob
                                              Urbit Developers
                                              • Hoon

                                                • Overview
                                                • Cheat Sheet
                                                • Irregular forms
                                                • Hoon Errors
                                                • Hoon Style Guide
                                                • Basic Types
                                                • Advanced Types
                                                • Auras
                                                • Standard Library

                                                  • 1a: Basic Arithmetic
                                                  • 1b: Tree Addressing
                                                  • 1c: Molds and Mold-Builders
                                                  • 2a: Unit Logic
                                                  • 2b: List Logic
                                                  • 2c: Bit Arithmetic
                                                  • 2d: Bit Logic
                                                  • 2e: Insecure Hashing
                                                  • 2f: Noun Ordering
                                                  • 2g: Unsigned Powers
                                                  • 2h: Set Logic
                                                  • 2i: Map Logic
                                                  • 2j: Jar and Jug Logic
                                                  • 2k: Queue Logic
                                                  • 2l: Container from Container
                                                  • 2m: Container from Noun
                                                  • 2n: Functional Hacks
                                                  • 2o: Normalizing Containers
                                                  • 2p: Serialization
                                                  • 2q: Molds and Mold-Builders
                                                  • 3a: Modular and Signed Ints
                                                  • 3b: Floating Point
                                                  • 3c: Urbit Time
                                                  • 3d: SHA Hash Family
                                                  • 3e: AES encryption (Removed)
                                                  • 3f: Scrambling
                                                  • 3g: Molds and Mold-Builders
                                                  • 4a: Exotic Bases
                                                  • 4b: Text Processing
                                                  • 4c: Tank Printer
                                                  • 4d: Parsing (Tracing)
                                                  • 4e: Parsing (Combinators)
                                                  • 4f: Parsing (Rule-Builders)
                                                  • 4g: Parsing (Outside Caller)
                                                  • 4h: Parsing (ASCII Glyphs)
                                                  • 4i: Parsing (Useful Idioms)
                                                  • 4j: Parsing (Bases and Base Digits)
                                                  • 4k: Atom Printing
                                                  • 4l: Atom Parsing
                                                  • 4m: Formatting Functions
                                                  • 4n: Virtualization
                                                  • 4o: Molds
                                                  • 5a: Compiler Utilities
                                                  • 5b: Macro Expansion
                                                  • 5c: Compiler Backend & Prettyprinter
                                                  • 5d: Parser
                                                  • 5e: Molds and mold builders
                                                  • 5f: Profiling support
                                                  • Runes

                                                    • Atoms and strings
                                                    • Nock . ('dot')
                                                    • Wild ! ('zap')
                                                    • Change Subject = ('tis')
                                                    • Conditionals ? ('wut')
                                                    • Cores | ('bar')
                                                    • Arms + ('lus')
                                                    • Cells : ('col')
                                                    • Calls % ('cen')
                                                    • Casts ^ ('ket')
                                                    • Structures $ ('buc')
                                                    • Make ; ('mic')
                                                    • Hints ~ ('sig')
                                                    • Imports / ('fas')
                                                    • Terminators -- and ==
                                                    • Limbs and wings

                                                      • Limbs
                                                      • Wings
                                                      • Zuse

                                                        • Table of Contents
                                                        • 2d(1-5): To JSON, Wains
                                                        • 2d(6): From JSON
                                                        • 2d(7): From JSON (unit)
                                                        • 2e(2-3): Print & Parse JSON
                                                      • Arvo

                                                        • Overview
                                                        • Ames

                                                          • Overview
                                                          • Cryptography
                                                          • API Reference
                                                          • Scry Reference
                                                          • Data Types
                                                          • Behn

                                                            • Overview
                                                            • API Reference
                                                            • Scry Reference
                                                            • Examples
                                                            • Clay

                                                              • Overview
                                                              • Architecture
                                                              • Using Clay
                                                              • Data Types
                                                              • Scry Reference
                                                              • API Reference
                                                              • Examples
                                                              • Marks

                                                                • Overview
                                                                • Writing Marks
                                                                • Using Marks
                                                                • Examples
                                                              • Dill

                                                                • Overview
                                                                • API Reference
                                                                • Scry Reference
                                                                • Data Types
                                                                • Eyre

                                                                  • Overview
                                                                  • External API Reference
                                                                  • Internal API Reference
                                                                  • Scry Reference
                                                                  • Data Types
                                                                  • Guide
                                                                  • Gall

                                                                    • Overview
                                                                    • API Reference
                                                                    • Data Types
                                                                    • Threads Reference
                                                                    • Iris

                                                                      • Overview
                                                                      • API Reference
                                                                      • Data Types
                                                                      • Example
                                                                      • Jael

                                                                        • Overview
                                                                        • API Reference
                                                                        • Scry Reference
                                                                        • Data Types
                                                                        • Examples
                                                                        • Threads

                                                                          • Overview
                                                                          • HTTP API
                                                                          • Reference
                                                                          • Gall

                                                                            • Start Thread
                                                                            • Take Result
                                                                            • Take Facts
                                                                            • Stop Thread
                                                                            • Poke Thread
                                                                            • Examples

                                                                              • Fetch JSON
                                                                              • Child Thread
                                                                              • Main-loop
                                                                              • Poke Agent
                                                                              • Scry
                                                                              • Take Fact
                                                                            • Concepts

                                                                              • Scries
                                                                              • Subscriptions
                                                                              • Tutorials

                                                                                • Move Trace
                                                                                • Reference

                                                                                  • Cryptography
                                                                                  • Filesystem Hierarchy
                                                                                • Nock

                                                                                  • Nock Definition
                                                                                  • Explanation
                                                                                  • Example
                                                                                  • Implementations
                                                                                  • Vere

                                                                                    • C Runtime System
                                                                                    • Land of Nouns
                                                                                    • API overview by prefix
                                                                                    • C in Urbit
                                                                                    • Writing Jets
                                                                                    • Cryptography
                                                                                    • Azimuth

                                                                                      • Overview
                                                                                      • Urbit HD Wallet
                                                                                      • Azimuth Data Flow
                                                                                      • Azimuth.eth
                                                                                      • Ecliptic.eth
                                                                                      • Advanced Azimuth Tools
                                                                                      • Life and Rift
                                                                                      • Layer 2

                                                                                        • Layer 2 Overview
                                                                                        • Layer 2 Actions
                                                                                        • Transaction Format
                                                                                        • Rollers
                                                                                        • Roller HTTP RPC-API
                                                                                        • Custom Roller Tutorial
                                                                                      • Glossary

                                                                                        • Ames
                                                                                        • Aqua
                                                                                        • Arm
                                                                                        • Arvo
                                                                                        • Atom
                                                                                        • Azimuth
                                                                                        • Battery
                                                                                        • Behn
                                                                                        • Bridge
                                                                                        • Censures
                                                                                        • chat
                                                                                        • Claims
                                                                                        • Clay
                                                                                        • Comet
                                                                                        • Core
                                                                                        • Delegated Sending
                                                                                        • Desk
                                                                                        • Dill
                                                                                        • Document Proposal
                                                                                        • Dojo
                                                                                        • Door
                                                                                        • Ecliptic
                                                                                        • Event Log
                                                                                        • Eyre
                                                                                        • Galaxy
                                                                                        • Gall
                                                                                        • Gate
                                                                                        • HD Wallet
                                                                                        • Hoon
                                                                                        • Invite Tree
                                                                                        • Iris
                                                                                        • Jael
                                                                                        • Keyfile
                                                                                        • Khan
                                                                                        • Landscape
                                                                                        • Mark
                                                                                        • Moon
                                                                                        • Nock
                                                                                        • Noun
                                                                                        • OTA Updates
                                                                                        • Payload
                                                                                        • pH
                                                                                        • Pier
                                                                                        • Pill
                                                                                        • Planet
                                                                                        • Proxies
                                                                                        • Replay
                                                                                        • Factory Reset
                                                                                        • Naive rollups
                                                                                        • Sail/Udon
                                                                                        • Senate
                                                                                        • Ship
                                                                                        • ship.arvo.network
                                                                                        • Star
                                                                                        • |sync
                                                                                        • Trap
                                                                                        • Upgrade Proposal
                                                                                        • Vane
                                                                                        • Vere
                                                                                        • Voting
                                                                                        • Wallet-Generator
                                                                                        • Additional

                                                                                          • Cryptography
                                                                                          • Software Distribution

                                                                                            • Overview
                                                                                            • Docket File
                                                                                            • Glob
                                                                                          Reference/Hoon/Standard Library

                                                                                          4i: Parsing (Useful Idioms)

                                                                                          ++alf

                                                                                          Alphabetic characters

                                                                                          Parse alphabetic characters, both upper and lowercase.

                                                                                          Source

                                                                                          ++ alf ;~(pose low hig)

                                                                                          Examples

                                                                                          > (scan "a" alf)
                                                                                          'a'
                                                                                          > (scan "A" alf)
                                                                                          'A'
                                                                                          > `tape`(scan "AaBbCc" (star alf))
                                                                                          "AaBbCc"

                                                                                          ++aln

                                                                                          Alphanumeric characters

                                                                                          Parse alphanumeric characters - both alphabetic characters and numbers.

                                                                                          Source

                                                                                          ++ aln ;~(pose low hig nud)

                                                                                          Examples

                                                                                          > (scan "0" aln)
                                                                                          '0'
                                                                                          > `tape`(scan "alf42" (star aln))
                                                                                          "alf42"

                                                                                          ++alp

                                                                                          Alphanumeric and -

                                                                                          Parse alphanumeric strings and hep, "-".

                                                                                          Source

                                                                                          ++ alp ;~(pose low hig nud hep)

                                                                                          Examples

                                                                                          > (scan "7" alp)
                                                                                          '7'
                                                                                          > (scan "s" alp)
                                                                                          's'
                                                                                          > `tape`(scan "123abc-" (star alp))
                                                                                          "123abc-"

                                                                                          ++bet

                                                                                          Axis syntax -, +

                                                                                          Parse the hep and lus axis syntax.

                                                                                          Source

                                                                                          ++ bet ;~(pose (cold 2 hep) (cold 3 lus))

                                                                                          Examples

                                                                                          > (scan "-" bet)
                                                                                          2
                                                                                          > (scan "+" bet)
                                                                                          3

                                                                                          ++bin

                                                                                          Binary to atom

                                                                                          Parse a tape of binary (0s and 1s) and produce its atomic representation.

                                                                                          Source

                                                                                          ++ bin (bass 2 (most gon but))

                                                                                          Examples

                                                                                          > (scan "0000" bin)
                                                                                          0
                                                                                          > (scan "0001" bin)
                                                                                          1
                                                                                          > (scan "0010" bin)
                                                                                          2
                                                                                          > (scan "100000001111" bin)
                                                                                          2.063

                                                                                          ++but

                                                                                          Binary digit

                                                                                          Parse a single binary digit.

                                                                                          Source

                                                                                          ++ but (cook |=(a=@ (sub a '0')) (shim '0' '1'))

                                                                                          Examples

                                                                                          > (scan "0" but)
                                                                                          0
                                                                                          > (scan "1" but)
                                                                                          1
                                                                                          > (scan "01" but)
                                                                                          ! {1 2}
                                                                                          ! 'syntax-error'
                                                                                          ! exit
                                                                                          > (scan "01" (star but))
                                                                                          ~[0 1]

                                                                                          ++cit

                                                                                          Octal digit

                                                                                          Parse a single octal digit.

                                                                                          Source

                                                                                          ++ cit (cook |=(a=@ (sub a '0')) (shim '0' '7'))

                                                                                          Examples

                                                                                          > (scan "1" cit)
                                                                                          1
                                                                                          > (scan "7" cit)
                                                                                          7
                                                                                          > (scan "8" cit)
                                                                                          ! {1 1}
                                                                                          ! 'syntax-error'
                                                                                          ! exit
                                                                                          > (scan "60" (star cit))
                                                                                          ~[6 0]

                                                                                          ++dem

                                                                                          Decimal to atom

                                                                                          Parse a decimal number to an atom.

                                                                                          Source

                                                                                          ++ dem (bass 10 (most gon dit))

                                                                                          Examples

                                                                                          > (scan "7" dem)
                                                                                          7
                                                                                          > (scan "42" dem)
                                                                                          42
                                                                                          > (scan "150000000" dem)
                                                                                          150.000.000
                                                                                          > (scan "12456" dem)
                                                                                          12.456

                                                                                          ++dit

                                                                                          Decimal digit

                                                                                          Parse a single decimal digit.

                                                                                          Source

                                                                                          ++ dit (cook |=(a=@ (sub a '0')) (shim '0' '9'))

                                                                                          Examples

                                                                                          > (scan "7" dit)
                                                                                          7
                                                                                          > (scan "42" (star dit))
                                                                                          ~[4 2]
                                                                                          > (scan "26000" (star dit))
                                                                                          ~[2 6 0 0 0]

                                                                                          ++dog

                                                                                          . optional gap

                                                                                          Dot followed by an optional gap, used with numbers.

                                                                                          Source

                                                                                          ++ dog ;~(plug dot gay)

                                                                                          Examples

                                                                                          > (scan "." dog)
                                                                                          ['.' ~]
                                                                                          > (scan "a. " ;~(pfix alf dog))
                                                                                          ['.' ~]

                                                                                          ++dof

                                                                                          - optional gap

                                                                                          Hep followed by an optional gap, used with @p & @q syntax.

                                                                                          Source

                                                                                          ++ dof ;~(plug hep gay)

                                                                                          Examples

                                                                                          > (scan "-" dof)
                                                                                          ['-' ~]
                                                                                          > (scan "- " dof)
                                                                                          ['-' ~]

                                                                                          ++doh

                                                                                          @p separator

                                                                                          Phonetic base phrase separator

                                                                                          Source

                                                                                          ++ doh ;~(plug ;~(plug hep hep) gay)

                                                                                          Examples

                                                                                          > (scan "--" doh)
                                                                                          [['-' '-'] ~]
                                                                                          > (scan "-- " doh)
                                                                                          [['-' '-'] ~]

                                                                                          ++dun

                                                                                          -- to ~

                                                                                          Parse phep, --, to null, ~.

                                                                                          Source

                                                                                          ++ dun (cold ~ ;~(plug hep hep))

                                                                                          Examples

                                                                                          > (scan "--" dun)
                                                                                          ~

                                                                                          ++duz

                                                                                          == to ~

                                                                                          Parse stet, ==, to null ~.

                                                                                          Source

                                                                                          ++ duz (cold ~ ;~(plug tis tis))

                                                                                          Examples

                                                                                          > (scan "==" duz)
                                                                                          ~

                                                                                          ++gah

                                                                                          Newline or ' '

                                                                                          Whitespace component, either newline or space.

                                                                                          Source

                                                                                          ++ gah (mask [`@`10 ' ' ~])

                                                                                          Examples

                                                                                          > `tape`(scan " \0a \0a" (star gah))
                                                                                          " \0a \0a"

                                                                                          ++gap

                                                                                          Plural whitespace

                                                                                          Separates tall runes

                                                                                          Source

                                                                                          ++ gap (cold ~ ;~(plug gaq (star ;~(pose vul gah))))

                                                                                          Examples

                                                                                          > `tape`(scan " \0a \0a" gap)
                                                                                          ""
                                                                                          > (scan "\0a \0a XYZ" ;~(pfix gap (jest 'XYZ')))
                                                                                          'XYZ'

                                                                                          ++gaq

                                                                                          End of line

                                                                                          Two spaces, a newline, or comment.

                                                                                          Source

                                                                                          ++ gaq ;~ pose
                                                                                          (just `@`10)
                                                                                          ;~(plug gah ;~(pose gah vul))
                                                                                          vul
                                                                                          ==

                                                                                          Examples

                                                                                          > (scan "123\0a" ;~(sfix dem gaq))
                                                                                          123
                                                                                          > (scan "123 :: foo\0a" ;~(sfix dem gaq))
                                                                                          123

                                                                                          ++gaw

                                                                                          Classic whitespace

                                                                                          Terran whitespace.

                                                                                          Source

                                                                                          ++ gaw (cold ~ (star ;~(pose vul gah)))

                                                                                          Examples

                                                                                          > (scan " \0a :: foo \0a" gaw)
                                                                                          ~
                                                                                          > (scan " " gaw)
                                                                                          ~
                                                                                          > (scan "\0a" gaw)
                                                                                          ~

                                                                                          ++gay

                                                                                          Optional gap

                                                                                          Optional gap.

                                                                                          Source

                                                                                          ++ gay ;~(pose gap (easy ~))

                                                                                          Examples

                                                                                          > (scan " " gay)
                                                                                          ~
                                                                                          > (scan " " gay)
                                                                                          ~
                                                                                          > (scan "\0a" gay)
                                                                                          ~
                                                                                          > (scan "" gay)
                                                                                          ~

                                                                                          ++gon

                                                                                          Long numbers

                                                                                          Parse long numbers - Numbers which wrap around the shell with the line

                                                                                          Source

                                                                                          ++ gon ;~(pose ;~(plug bas gay fas) (easy ~))

                                                                                          Examples

                                                                                          > 'abc\
                                                                                          /def'
                                                                                          'abcdef'
                                                                                          > (scan "\\\0a/" gon)
                                                                                          ['\\' ~ '/']

                                                                                          ++gul

                                                                                          Axis syntax < or >

                                                                                          Parse the axis gal and gar axis syntax.

                                                                                          Source

                                                                                          ++ gul ;~(pose (cold 2 gal) (cold 3 gar))

                                                                                          Examples

                                                                                          > (scan "<" gul)
                                                                                          2
                                                                                          > (scan ">" gul)
                                                                                          3

                                                                                          ++hex

                                                                                          Hex to atom

                                                                                          Parse any hexadecimal number to an atom.

                                                                                          Source

                                                                                          ++ hex (bass 16 (most gon hit))

                                                                                          Examples

                                                                                          > (scan "a" hex)
                                                                                          10
                                                                                          > (scan "A" hex)
                                                                                          10
                                                                                          > (scan "2A" hex)
                                                                                          42
                                                                                          > (scan "1ee7" hex)
                                                                                          7.911
                                                                                          > (scan "1EE7" hex)
                                                                                          7.911
                                                                                          > (scan "1EE7F7" hex)
                                                                                          2.025.463
                                                                                          > `@ux`(scan "1EE7F7" hex)
                                                                                          0x1e.e7f7

                                                                                          ++hig

                                                                                          Uppercase

                                                                                          Parse a single uppercase letter.

                                                                                          Source

                                                                                          ++ hig (shim 'A' 'Z')

                                                                                          Examples

                                                                                          > (scan "G" hig)
                                                                                          'G'
                                                                                          > (scan "ABCDEFGHIJKLMNOPQRSTUVWXYZ" (star hig))
                                                                                          "ABCDEFGHIJKLMNOPQRSTUVWXYZ"

                                                                                          ++hit

                                                                                          Hex digits

                                                                                          Parse a single hexadecimal digit.

                                                                                          Source

                                                                                          ++ hit ;~ pose
                                                                                          dit
                                                                                          (cook |=(a=char (sub a 87)) (shim 'a' 'f'))
                                                                                          (cook |=(a=char (sub a 55)) (shim 'A' 'F'))
                                                                                          ==

                                                                                          Examples

                                                                                          > (scan "a" hit)
                                                                                          10
                                                                                          > (scan "A" hit)
                                                                                          10
                                                                                          > (scan "2A" (star hit))
                                                                                          ~[2 10]

                                                                                          ++iny

                                                                                          Indentation block

                                                                                          Apply rule to indented block starting at current column number, omitting the leading whitespace.

                                                                                          Accepts

                                                                                          sef is a rule

                                                                                          Produces

                                                                                          A rule.

                                                                                          Source

                                                                                          ++ iny
                                                                                          |* sef=rule
                                                                                          |= nail ^+ (sef)
                                                                                          =+ [har tap]=[p q]:+<
                                                                                          =+ lev=(fil 3 (dec q.har) ' ')
                                                                                          =+ eol=(just `@t`10)
                                                                                          =+ =- roq=((star ;~(pose prn ;~(sfix eol (jest lev)) -)) har tap)
                                                                                          ;~(simu ;~(plug eol eol) eol)
                                                                                          ?~ q.roq roq
                                                                                          =+ vex=(sef har(q 1) p.u.q.roq)
                                                                                          =+ fur=p.vex(q (add (dec q.har) q.p.vex))
                                                                                          ?~ q.vex vex(p fur)
                                                                                          =- vex(p fur, u.q -)
                                                                                          :+ &3.vex
                                                                                          &4.vex(q.p (add (dec q.har) q.p.&4.vex))
                                                                                          =+ res=|4.vex
                                                                                          |- ?~ res |4.roq
                                                                                          ?. =(10 -.res) [-.res $(res +.res)]
                                                                                          (welp [`@t`10 (trip lev)] $(res +.res))

                                                                                          Examples

                                                                                          > `tape`(scan " foo\0a bar" ;~(pfix ace ace ace (iny (star ;~(pose prn (just '\0a'))))))
                                                                                          "foo\0abar"

                                                                                          Discussion

                                                                                          Note the amount of indentation whitespace to be stripped from the beginning of each line is determined by the value of q (the column) in the hair when ++iny is first called. This means something like the pfix expression in the example above is necessary to set the level of indentation. Additionally, the rule given to ++iny must consume the whole line including the line ending.


                                                                                          ++low

                                                                                          Lowercase

                                                                                          Parse a single lowercase letter.

                                                                                          Source

                                                                                          ++ low (shim 'a' 'z')

                                                                                          Examples

                                                                                          > (scan "g" low)
                                                                                          'g'

                                                                                          ++mes

                                                                                          Hexbyte

                                                                                          Parse a hexbyte.

                                                                                          Source

                                                                                          ++ mes %+ cook
                                                                                          |=({a/@ b/@} (add (mul 16 a) b))
                                                                                          ;~(plug hit hit)

                                                                                          Examples

                                                                                          > (scan "2A" mes)
                                                                                          42
                                                                                          > (scan "42" mes)
                                                                                          66

                                                                                          ++nix

                                                                                          Letters and underscore

                                                                                          Parse Letters and _.

                                                                                          Source

                                                                                          ++ nix (boss 256 (star ;~(pose aln cab)))

                                                                                          Examples

                                                                                          > `@t`(scan "as_me" nix)
                                                                                          'as_me'

                                                                                          ++nud

                                                                                          Numeric

                                                                                          Parse a numeric character - A number.

                                                                                          Source

                                                                                          ++ nud (shim '0' '9')

                                                                                          Examples

                                                                                          > (scan "0" nud)
                                                                                          '0'
                                                                                          > (scan "7" nud)
                                                                                          '7'

                                                                                          ++prn

                                                                                          Printable character

                                                                                          Parse any printable character.

                                                                                          Source

                                                                                          ++ prn ;~(less (just `@`127) (shim 32 256))

                                                                                          Examples

                                                                                          > (scan "h" prn)
                                                                                          'h'
                                                                                          > (scan "!" prn)
                                                                                          '!'
                                                                                          > (scan "\01" prn)
                                                                                          ! {1 1}
                                                                                          ! exit

                                                                                          ++qat

                                                                                          Chars in blockcord

                                                                                          Parse a single character contained in a mult-line cord block.

                                                                                          Source

                                                                                          ++ qat ;~ pose
                                                                                          prn
                                                                                          ;~(less ;~(plug (just `@`10) soz) (just `@`10))
                                                                                          ==

                                                                                          Examples

                                                                                          > ^- tape
                                                                                          %+ scan
                                                                                          "'''\0aabc\0adef\0aghi\0a'''"
                                                                                          %+ ifix
                                                                                          :- ;~(plug soz (just `@`10))
                                                                                          ;~(plug (just `@`10) soz)
                                                                                          (star qat)
                                                                                          "abc\0adef\0aghi"

                                                                                          ++qit

                                                                                          Chars in cord

                                                                                          Parse an individual character to its cord atom representation. Escaped characters are converted to the value they represent.

                                                                                          Source

                                                                                          ++ qit ;~ pose :: chars in a cord
                                                                                          ;~(less bas soq prn)
                                                                                          ;~(pfix bas ;~(pose bas soq mes)) :: escape chars
                                                                                          ==

                                                                                          Examples

                                                                                          > (scan "%" qit)
                                                                                          '%'
                                                                                          > `tape`(scan "cord" (star qit))
                                                                                          "cord"
                                                                                          > `tape`(scan "\\0a" (star qit))
                                                                                          "\0a"

                                                                                          ++qut

                                                                                          Cord

                                                                                          Parse single-soq cord with \{gap}/ anywhere in the middle, or triple-single quote (aka triple-soq) cord, between which must be in an indented block.

                                                                                          Source

                                                                                          ++ qut ;~ simu soq
                                                                                          ;~ pose
                                                                                          ;~ less soz
                                                                                          (ifix [soq soq] (boss 256 (more gon qit)))
                                                                                          ==
                                                                                          =+ hed=;~(pose ;~(plug (plus ace) vul) (just '\0a'))
                                                                                          %- iny %+ ifix
                                                                                          :- ;~(plug soz hed)
                                                                                          ;~(plug (just '\0a') soz)
                                                                                          (boss 256 (star qat))
                                                                                          ==
                                                                                          ==

                                                                                          Examples

                                                                                          > `@t`(scan "'cord'" qut)
                                                                                          'cord'
                                                                                          > `@t`(scan "'''\0aabc\0adef\0a'''" qut)
                                                                                          'abc\0adef'

                                                                                          ++soz

                                                                                          Delimiting '''

                                                                                          Parse a triple-single quote, used for multiline strings.

                                                                                          Source

                                                                                          ++ soz ;~(plug soq soq soq)

                                                                                          Examples

                                                                                          > (scan "'''" soz)
                                                                                          ['\'' '\'' '\'']

                                                                                          ++sym

                                                                                          Term

                                                                                          A term: a lowercase letter, followed by letters, numbers, or -.

                                                                                          Source

                                                                                          ++ sym
                                                                                          %+ cook
                                                                                          |=(a=tape (rap 3 ^-((list @) a)))
                                                                                          ;~(plug low (star ;~(pose nud low hep)))

                                                                                          Examples

                                                                                          > `term`(scan "sam-2" sym)
                                                                                          %sam-2

                                                                                          ++mixed-case-symbol

                                                                                          Mixed-case term

                                                                                          The same as ++sym but allowing uppercase letters.

                                                                                          Source

                                                                                          ++ mixed-case-symbol
                                                                                          %+ cook
                                                                                          |=(a=tape (rap 3 ^-((list @) a)))
                                                                                          ;~(plug alf (star alp))

                                                                                          Examples

                                                                                          > `term`(scan "sAm-2" mixed-case-symbol)
                                                                                          %sAm-2

                                                                                          ++ven

                                                                                          +>- axis syntax

                                                                                          Axis syntax parser

                                                                                          Source

                                                                                          ++ ven ;~ (comp |=([a=@ b=@] (peg a b)))
                                                                                          bet
                                                                                          =+ hom=`?`|
                                                                                          |= tub=nail
                                                                                          ^- (like @)
                                                                                          =+ vex=?:(hom (bet tub) (gul tub))
                                                                                          ?~ q.vex
                                                                                          [p.tub [~ 1 tub]]
                                                                                          =+ wag=$(p.tub p.vex, hom !hom, tub q.u.q.vex)
                                                                                          ?> ?=(^ q.wag)
                                                                                          [p.wag [~ (peg p.u.q.vex p.u.q.wag) q.u.q.wag]]
                                                                                          ==

                                                                                          Examples

                                                                                          > (scan "->+" ven)
                                                                                          11
                                                                                          > (scan "->+<-" ven)
                                                                                          44

                                                                                          ++vit

                                                                                          Base64 digit

                                                                                          Parse a standard base64 digit.

                                                                                          Source

                                                                                          ++ vit
                                                                                          ;~ pose
                                                                                          (cook |=(a=@ (sub a 65)) (shim 'A' 'Z'))
                                                                                          (cook |=(a=@ (sub a 71)) (shim 'a' 'z'))
                                                                                          (cook |=(a=@ (add a 4)) (shim '0' '9'))
                                                                                          (cold 62 (just '-'))
                                                                                          (cold 63 (just '+'))
                                                                                          ==

                                                                                          Examples

                                                                                          > (scan "C" vit)
                                                                                          2
                                                                                          > (scan "c" vit)
                                                                                          28
                                                                                          > (scan "2" vit)
                                                                                          54
                                                                                          > (scan "-" vit)
                                                                                          62

                                                                                          ++vul

                                                                                          Comments to null

                                                                                          Parse comments and produce a null. Note that a comment must be ended with a newline character.

                                                                                          Source

                                                                                          ++ vul %+ cold ~
                                                                                          ;~ plug col col
                                                                                          (star prn)
                                                                                          (just `@`10)
                                                                                          ==

                                                                                          Examples

                                                                                          > (scan "::this is a comment \0a" vul)
                                                                                          ~
                                                                                          > (scan "::this is a comment " vul)
                                                                                          ! {1 21}
                                                                                          ! exit

                                                                                          <-

                                                                                          4h: Parsing (ASCII Glyphs)

                                                                                          4j: Parsing (Bases and Base Digits)

                                                                                          ->

                                                                                          Edit this page on GitHub