first4 ( seq -- first second third fourth )
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
third	the third element
fourth	the fourth element

Word description
Pushes the first four elements of a sequence.

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

Definition

USING: kernel sequences.private ;

IN: sequences

: first4 ( seq -- first second third fourth )
    3 swap bounds-check nip first4-unsafe ; inline