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

Inputs
seqa sequence


Outputs
firstthe first element of the sequence


Word description
Outputs the first element of the sequence.

Errors
Throws an error if the sequence is empty.

See also
first2, last, last2, but-last, but-last-slice, rest, rest-slice

Definition
USING: kernel ;

IN: sequences

: first ( seq -- first ) 0 swap nth ; inline