unless-zero ( ... n quot: ( ... n -- ... ) -- ... ) (original) (raw)

Vocabulary
math

Inputs

n a number
quot the second quotation of an if-zero

Outputs
None

Word description
Makes an implicit check if the number is zero. A zero is dropped. Otherwise, the quot is called on the number.

Examples
This word is equivalent to if-zero with an empty first quotation:

USING: sequences math prettyprint ; 3 [ ] [ sq . ] if-zero
9

USING: sequences math prettyprint ; 3 [ sq . ] unless-zero
9

See also
if-zero, when-zero, until-zero

Definition

USING: kernel ;

IN: math

: unless-zero ( ... n quot: ( ... n -- ... ) -- ... )
[ ] swap if-zero ; inline