+{ $description "Calls a predicate quotation on each key of the input assoc. If the test yields true, the key/value pair is added to " { $snippet "true-assoc" } "; if false, it's added to " { $snippet "false-assoc" } "." } ;
{ $description "Tests if the assoc contains an entry satisfying a predicate by applying the quotation to each entry in turn. Iteration stops if an entry is found for which the quotation outputs a true value." } ;
{ $values { "key" "a key" } { "assoc" assoc } { "quot" { $quotation "( key -- value )" } } { "value" "a previously-retained or freshly-computed value" } }
-{ $description "If the key is present in the assoc, outputs the associated value, otherwise calls the quotation to produce a value and stores the key/value pair into the assoc." }
+{ $description "If the key is present in the assoc, outputs the associated value, otherwise calls the quotation to produce a value and stores the key/value pair into the assoc. Returns a value either looked up or newly stored in the assoc." }
+{ $side-effects "assoc" } ;
+
+HELP: 2cache
+{ $values { "key1" "a key" } { "key2" "a key" } { "assoc" assoc } { "quot" { $quotation "( key -- value )" } } { "value" "a previously-retained or freshly-computed value" } }
+{ $description "If a single key composed of the input keys is present in the assoc, outputs the associated value, otherwise calls the quotation to produce a value and stores the keys/value pair into the assoc. Returns the value stored in the assoc. Returns a value either looked up or newly stored in the assoc." }