Word description Defines a new hook word in the current vocabulary. Hook words are generic words which dispatch on the value of a variable, so methods are defined with M:. Hook words differ from other generic words in that the dispatch value is removed from the stack before the chosen method is called.
Examples
USING: io namespaces ;
IN: scratchpad
SYMBOL: transport
TUPLE: land-transport ;
TUPLE: air-transport ;
HOOK: deliver transport ( destination -- )
M: land-transport deliver "Land delivery to " write print ;
M: air-transport deliver "Air delivery to " write print ;
T{ air-transport } transport set
"New York City" deliver Air delivery to New York City
Notes Hook words are really just generic words with a custom method combination (see Custom method combination).