? ( ? true false -- true/false )
Factor handbook » The language » Combinators » Conditional combinators
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Vocabulary
kernel

Inputs
?a boolean
truean object
falsean object


Outputs
true/falsean object


Word description
Chooses between two values depending on the boolean value of ?.

Examples
USING: io kernel math ; 3 4 < "3 is smaller than 4" "3 is not smaller than 4" ? print
3 is smaller than 4

USING: io kernel math ; 4 3 < "4 is smaller than 3" "4 is not smaller than 3" ? print
4 is not smaller than 3


Definition
IN: kernel

: ? ( ? true false -- true/false ) rot [ drop ] [ nip ] if ;
inline