urbit/base/pub/doc/hoon/runes/cl/clhp.md
2015-04-29 18:48:45 -04:00

1.4 KiB

colhep, :-, %clhp

Cell

:-, colhep, [%clhp p=twig q=twig] is a synthetic rune that produces the cell [p q].

Produces

Twig: [%clhp p=twig q=twig]

Sample

p is a twig. q is a twig.

Tall form

:-  p
    q

Wide form

:-(p q)

Irregular form

[p q]

Examples

~zod/try=> :-(1 2)
[1 2]
~zod/try=> :-  'a'
           %b
['a' %b]

This is the most straightforward case of :-, producing a cell of static data in either tall or wide form.

/~zod/try=> 
    :-  (add 2 2)
    |-  (div 4 2)
[4 2]

Most commonly :- helps to organize code, allowing you to produce a cell from nested computation.

Some obscure :- irregular forms.

Moveme: irregular form doc

Infix ^

~zod/main=/app> 1^2^3
[1 2 3]

a^b is equivalent to :- a b

Infix /

~zod/main=/app> a/1
[%a 1]
~zod/main=/app> a/'twig'
[%a 'twig']

Like ^, but first item must be a term, and is cubed. Used to construct paths and fronds.

Prefix `, postfix ~

~zod/main=/app> ````20
[~ ~ ~ ~ 20]
~zod/main=/app> [42 30]~
[[42 30] ~]

Complimenting each other, these construct pairs with nil in the head and tail respectively. Multiple postfix ~ do not work for unknown reasons.