trim-head ( ... seq quot: ( ... elt -- ... ? ) -- ... newseq )
Factor handbook » The language » Collections » Sequence operations » Trimming sequences

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Vocabulary
sequences

Inputs

seq	a sequence
quot	a quotation

Outputs

newseq

a sequence

Word description
Removes elements starting from the left side of a sequence if they match a predicate. Once an element does not match, the test stops and the rest of the sequence is left on the stack as a new sequence.

Examples

USING: prettyprint math sequences ; { 0 0 1 2 3 0 0 } [ zero? ] trim-head .
{ 1 2 3 0 0 }

See also
trim, trim-slice, trim-head-slice, trim-tail, trim-tail-slice

Definition

USING: sequences.private ;

IN: sequences

: trim-head
    ( ... seq quot: ( ... elt -- ... ? ) -- ... newseq )
    (trim-head) tail ; inline