mirror of
https://github.com/ilyakooo0/urbit.git
synced 2024-12-20 21:31:32 +03:00
74 lines
1.5 KiB
Markdown
74 lines
1.5 KiB
Markdown
bartar, `|*`, %brtr
|
|
============================
|
|
|
|
Wet gate
|
|
|
|
`|*` is a synthetic hoon that produces a [wet]() [gate]() with sample
|
|
[`$*(p)`](), arm `q`. A gate is a core with one arm, [`$`](), the empty
|
|
name.
|
|
|
|
`|*` is similar to a function in the same way that `|=` is, but differs
|
|
in that it does type checking at runtime. With `|*`, the product type is
|
|
checked to be the same as the input type, rather than the sample tile.
|
|
|
|
See also
|
|
--------
|
|
|
|
bartis, `|=`, %brts
|
|
============================
|
|
|
|
Produces
|
|
--------
|
|
|
|
Twig: `[%brtr p=tile q=twig]`
|
|
|
|
Sample
|
|
------
|
|
|
|
`p` is a [tile](). `q` is a [twig]().
|
|
|
|
Tall form
|
|
---------
|
|
|
|
|* p
|
|
q
|
|
|
|
Wide form
|
|
---------
|
|
|
|
|*(p q)
|
|
|
|
Irregular form
|
|
--------------
|
|
|
|
None
|
|
|
|
Examples
|
|
--------
|
|
|
|
~zod/try=> %.('c' |*(a=@ a))
|
|
'c'
|
|
~zod/try=> %.('c' |=(a=@ a))
|
|
99
|
|
|
|
This is a concise way of understanding the difference between `|*` and
|
|
`|=`. We use `%.` in both cases to slam each gate with the sample `'c'`.
|
|
`|=` uses its tile `a=@` to cast `'c'` to an atom (`99` is the ASCII
|
|
code for `'c'`). `|*` simply ensures that the product type matches the
|
|
input sample type.
|
|
|
|
++ flop :: reverse
|
|
~/ %flop
|
|
|* a=(list)
|
|
=> .(a (homo a))
|
|
^+ a
|
|
=+ b=`_a`~
|
|
|-
|
|
?@ a
|
|
b
|
|
$(a t.a, b [i.a b])
|
|
|
|
In [`++flop`](), `|*` is used so the type information within the passed
|
|
in list is maintained. Without a `|*`, any cords would be cast to nouns
|
|
as in our previous example.
|