cond>quot ( assoc -- quot )
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case>quot ( default assoc -- quot )

Vocabulary
combinators

Inputs

assoc

a sequence of pairs of quotations

Outputs

quot	a quotation

Word description
Creates a quotation that when called, has the same effect as applying cond to assoc.

The generated quotation is more efficient than the naive implementation of cond, though, since it expands into a series of conditionals, and no iteration through assoc has to be performed.

Notes
This word is used behind the scenes to compile cond forms efficiently; it can also be called directly, which is useful for meta-programming.

Definition

USING: arrays kernel sequences ;

IN: combinators

: cond>quot ( assoc -- quot )
    [ dup pair? [ [ t ] swap 2array ] unless ] map reverse!
    [ no-cond ] swap alist>quot ;