pad-head ( seq n elt -- padded )
Factor handbook » The language » Collections » Sequence operations » Appending sequences

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Vocabulary
sequences

Inputs

seq	a sequence
n	a non-negative integer
elt	an object

Outputs

padded

a new sequence

Word description
Outputs a new sequence consisting of seq padded on the left with enough repetitions of elt to have the result be of length n.

Examples

USING: io sequences ; { "ab" "quux" } [ 5 CHAR: - pad-head print ] each
---ab -quux

Definition

USING: kernel sequences.private ;

IN: sequences

: pad-head ( seq n elt -- padded )
    [ swap dup append-as ] padding ;