urbit/pub/docs/dev/hoon/runes/ts/tsgl.md

tisgal, =<, %tsgl

Product as subject, inverse

=< is a synthetic rune that uses the product of q as the subject of p. =< is the inverse of =>. Use =< when your computation, q is lengthier and =< makes for more readable code.

See also

tisgar, =>, %tsgr

Produces

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

Sample

p and q are twigs.

Tall form

=<  p
    q

Wide form

=<(p q)

Irregular form

p:q

Examples

~zod/try=> b:[a=1 b=2 c=3]
2
~zod/try=> [. .]:(add 2 4)
[6 6]

In this simple example we first produce b from the tuple [a=1 b=2 c=3] using the irregular form of =<. Then we use . to produce our context from the computation (add 2 4) as a cell, [6 6].

~zod/try=> =<  lom
           |%
           ++  lom  (add 2 tak)
           ++  tak  4
           --
6

This example is a more common case, where we want to pull some specific value out of a longer computation. Here we use the tall form of =< to pull the arm lom from the core created with |%.