ndup ( n -- )
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dupn ( n -- quot )

Vocabulary
generalizations

Inputs

n	an integer

Outputs
None

Word description
A generalization of dup, 2dup and 3dup that can work for any number of items. The n topmost items on the stack will be copied and placed on the top of the stack.

Examples

USING: prettyprint generalizations kernel sequences.generalizations ; 1 2 3 4 4 ndup 8 narray .
{ 1 2 3 4 1 2 3 4 }

Some core words expressed in terms of ndup:

dup	1 ndup
2dup	2 ndup
3dup	3 ndup

Definition

USING: kernel ;

IN: generalizations

: ndup ( n -- ) [ [ npick ] curry ] keep call-n ; inline