v-optional ( str quot -- result )
Form validators

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Vocabulary
validators

Inputs

str	a string
quot	a quotation

Outputs

result

a string

Word description
If the string is non-empty, applies the quotation to the string, otherwise outputs the empty string.

Definition

USING: kernel sequences ;

IN: validators

: v-optional ( str quot -- result )
    over empty? [ 2drop f ] [ call ] if ; inline