first2 ( seq -- first second )
Factor handbook » The language » Collections » Sequence operations » Accessing sequence elements

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Vocabulary
sequences

Inputs

seq	a sequence

Outputs

first	the first element
second	the second element

Word description
Pushes the first two elements of a sequence.

Errors
Throws an error if the sequence has less than two elements.

See also
first, last, last2, but-last, but-last-slice, rest, rest-slice

Definition

USING: kernel sequences.private ;

IN: sequences

: first2 ( seq -- first second )
    1 swap bounds-check nip first2-unsafe ; inline