2j: Jar and Jug Logic • Reference • developers.urbit.org

`++ja`

Jar engine

A container arm for jar operation arms. A jar is a map of lists. The contained arms inherit the sample jar.

Accepts

a is a jar.

Produces

A core.

Source

++  ja
  =|  a=(tree (pair * (list)))  ::  (jar)
  |@

Examples

> ~(. ja (my [a+1 b+2 ~]))
< 2.ngd
  [   a
    ?(
      %~
      [ n=[?(p=%a p=%b) [email protected]]
        l=nlr([p=?(%a %b) [email protected]])
        r=nlr([p=?(%a %b) [email protected]])
      ]
    )
    <123.zao 46.hgz 1.pnw %140>
  ]
>

`++get:ja`

Grab value by key

Produces the list at key b in jar a.

Accepts

a is a jar, and is the sample of +ja.

b is a noun.

Produces

A list.

Source

++  get
  |*  b=*
  =+  c=(~(get by a) b)
  ?~(c ~ u.c)

Examples

> =j `(jar @t @ud)`(malt ~[['a' `(list @ud)`~[1 2 3]] ['b' `(list @ud)`~[4 5 6]]])
> j
{[p='b' q=~[4 5 6]] [p='a' q=~[1 2 3]]}

> `(list @ud)`(~(get ja j) 'a')
~[1 2 3]

> `(list @ud)`(~(get ja j) 'b')
~[4 5 6]

> `(list @ud)`(~(get ja j) 'c')
~

`++add:ja`

Prepend to list

Adds c to the head of the list at key b in jar a. If b does not exist in a, a new key-value pair is added with a list containing c.

Accepts

a is a jar, and is the sample of +ja.

b is a noun of the same type as the keys in a.

c is a noun of the same type the lists in a contain.

Produces

A jar.

Source

++  add
  |*  [b=* c=*]
  =+  d=(get b)
  (~(put by a) b [c d])

Examples

> =j `(jar @t @ud)`(malt ~[['a' `(list @ud)`~[1 2 3]] ['b' `(list @ud)`~[4 5 6]]])
> j
{[p='b' q=~[4 5 6]] [p='a' q=~[1 2 3]]}

> `(jar @t @ud)`(~(add ja j) 'b' 7)
{[p='b' q=~[7 4 5 6]] [p='a' q=~[1 2 3]]}

> `(jar @t @ud)`(~(add ja j) 'c' 8)
{[p='b' q=~[4 5 6]] [p='a' q=~[1 2 3]] [p='c' q=~[8]]}

`++ju`

Jug operations

Container arm for jug operation arms. A jug is a map of sets. The contained arms inherit its sample jug, a.

Accepts

a is a jug.

Produces

A core.

Source

++  ju
  =|  a=(tree (pair * (tree)))  ::  (jug)
  |@

Example

> =j `(jug @t @ud)`(malt ~[['a' (silt ~[1 2 3])] ['b' (silt ~[4 5 6])]])
> j
{[p='b' q={5 6 4}] [p='a' q={1 2 3}]}

> ~(. ju j)
<5.cws [a=nlr([[email protected] q=nlr(@ud)]) <123.zao 46.hgz 1.pnw %140>]>

`++del:ju`

Remove

Produces jug a with value c removed from set located at key b.

Accepts

a is a jug, and is the sample of +ju.

b is a noun of the same type as the keys in a.

c is a noun of the same type as the sets in a contain.

Source

++  del
  |*  [b=* c=*]
  ^+  a
  =+  d=(get b)
  =+  e=(~(del in d) c)
  ?~  e
    (~(del by a) b)
  (~(put by a) b e)

Examples

> j
{[p='b' q={5 6 4}] [p='a' q={1 2 3}]}

> `(jug @t @ud)`(~(del ju j) 'b' 6)
{[p='b' q={5 4}] [p='a' q={1 2 3}]}

> `(jug @t @ud)`(~(del ju j) 'b' 10)
{[p='b' q={5 6 4}] [p='a' q={1 2 3}]}

> `(jug @t @ud)`(~(del ju j) 'c' 10)
{[p='b' q={5 6 4}] [p='a' q={1 2 3}]}

`++gas:ju`

Concatenate

Add each of the key-value pairs in list b to jug a. The values in b are the type the sets in a contain. For keys in b that exist in a, the values will be added to their sets. For keys in b that don't exist in a, new keys and sets will be added.

Accepts

a is a jug, and is the sample of +ju.

b is a (list [p q]), where:

p is a noun, the type of the keys in a.
q is a noun, the type the sets in a contain.

Produces

A jug.

Source

++  gas
  |*  b=(list [p=* q=*])
  =>  .(b `(list _?>(?=([[* ^] ^] a) [p=p q=n.q]:n.a))`b)
  |-  ^+  a
  ?~  b
    a
  $(b t.b, a (put p.i.b q.i.b))

Examples

> =j `(jug @t @ud)`(malt ~[['a' (silt ~[1 2 3])] ['b' (silt ~[4 5 6])]])
> j
{[p='b' q={5 6 4}] [p='a' q={1 2 3}]}

> `(jug @t @ud)`(~(gas ju j) ~[['a' 10] ['a' 42] ['b' 999] ['c' 7]])
{[p='b' q={5 6 4 999}] [p='a' q={10 42 1 2 3}] [p='c' q={7}]}

`++get:ju`

Retrieve set

Produces a set retrieved from jug a using key b.

Accepts

a is a jug, and the sample of +ju.

b is key, a noun of the same type as the keys in a.

Produces

A set.

Source

++  get
  |*  b=*
  =+  c=(~(get by a) b)
  ?~(c ~ u.c)

Examples

> =j `(jug @t @ud)`(malt ~[['a' (silt ~[1 2 3])] ['b' (silt ~[4 5 6])]])
> j
{[p='b' q={5 6 4}] [p='a' q={1 2 3}]}

> `(set @ud)`(~(get ju j) 'a')
{1 2 3}

> `(set @ud)`(~(get ju j) 'b')
{5 6 4}

> `(set @ud)`(~(get ju j) 'c')
{}

`++has:ju`

Check contents

Computes whether a value c exists within the set located at key b with jug a, producing a flag.

Accepts

a is a jug, and the sample of +ju.

b is a noun of the same type as the keys in a.

c is a noun of the same type as the sets in a contain.

Produces

A ?.

Source

++  has
  |*  [b=* c=*]
  ^-  ?
  (~(has in (get b)) c)

Examples

> =j `(jug @t @ud)`(malt ~[['a' (silt ~[1 2 3])] ['b' (silt ~[4 5 6])]])
> j
{[p='b' q={5 6 4}] [p='a' q={1 2 3}]}

> (~(has ju j) 'b' 5)
%.y

> (~(has ju j) 'b' 10)
%.n

> (~(has ju j) 'c' 10)
%.n

`++put:ju`

Add key-set pair

Produces jug a with c added to the set located at key b. If b isn't a key in a, it will be added and a new set created containing c.

Accepts

a is a jug.

b is a noun, the type of the keys in a.

c is a noun, the type the sets in a contain.

Produces

A jug.

Source

++  put
  |*  [b=* c=*]
  ^+  a
  =+  d=(get b)
  (~(put by a) b (~(put in d) c))

Examples

> j
{[p='b' q={5 6 4}] [p='a' q={1 2 3}]}

> `(jug @t @ud)`(~(put ju j) 'c' 5)
{[p='b' q={5 6 4}] [p='a' q={1 2 3}] [p='c' q={5}]}

> `(jug @t @ud)`(~(put ju j) 'a' 4)
{[p='b' q={5 6 4}] [p='a' q={1 2 3 4}]}

> `(jug @t @ud)`(~(put ju j) 'a' 1)
{[p='b' q={5 6 4}] [p='a' q={1 2 3}]}