dupn ( n -- quot )
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Vocabulary
generalizations

Inputs

n	an integer

Outputs
None

Word description
Calls dup enough times that n references to the element at the top of the stack before dupn is called are on the top of the stack.

Notes
2 dupn is equivalent to dup. 1 dupn is a no-op. 0 dupn is equivalent to drop.

Definition

USING: kernel math ;

IN: generalizations

MACRO: dupn ( n -- quot )
    [ [ drop ] ] [ 1 - [ dup ] n*quot ] if-zero ;