compare ( ... obj1 obj2 quot: ( ... obj -- ... key ) -- ... <=> )
Factor handbook » The language » Objects » Linear order protocol

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Vocabulary
math.order

Inputs

obj1	an object
obj2	an object
quot	a quotation with stack effect ( ... obj -- ... key )

Outputs

<=>	an ordering specifier

Word description
Compares the results of applying the quotation to both objects via <=>.

Notes
The quotation is applied to the first object, then the second. It may update values below its input; computed keys are kept outside that row.

Examples

USING: kernel math.order prettyprint sequences ; "hello" "hi" [ length ] compare .
+gt+

See also
sort, sort-by, inv-sort-by, sort-keys, sort-values

Definition

USING: kernel ;

IN: math.order

: compare
    ( ... obj1 obj2 quot: ( ... obj -- ... key ) -- ... <=> )
    bi-curry@ [ call ] dip swap [ call ] dip swap <=> ; inline