Thun/implementations/Prolog/docs/reference/nullary.md

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## nullary
(Combinator)
Run a quoted program without using any stack values and leave the first item of the result on the stack.
... [P] nullary
---------------------
... A
### Definition
[stack] dip infra first
### Derivation
... [P] nullary
... [P] [stack] dip infra first
... stack [P] infra first
... [...] [P] infra first
... [A ...] first
... A
### Discussion
A very useful function that runs any other quoted function and returns
it's first result without disturbing the stack (under the quoted
program.)
### Crosslinks
[unary](#unary)
[binary](#binary)
[ternary](#ternary)