set-firstn ( n -- quot )
Generalized sequence words

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Vocabulary
sequences.generalizations

Inputs

n	an integer

Outputs
None

Word description
A generalization of set-first that sets the first n elements of a sequence from the top n elements of the stack.

Definition

USING: kernel math sequences ;

IN: sequences.generalizations

MACRO: set-firstn ( n -- quot )
    [ [ drop ] ] [
        [ 1 - ] keep [ [ swap bounds-check nip ] curry ] dip
        [ set-firstn-unsafe ] curry compose
    ] if-zero ;