USING: generic help ; HELP: define-typecheck "( class generic quot -- )" { $values { "class" "a class word" } { "generic" "a generic word" } { "quot" "a quotation" } } { $description "Defines a generic word with the " { $link standard-combination } " using dispatch position 0, and having one method on " { $snippet "class" } "." $terpri "This creates a definition analogous to the following code:" { $code "GENERIC: generic" "M: class generic quot ;" } "It checks if the top of the stack is an instance of " { $snippet "class" } ", and if so, executes the quotation. Delegation is respected." } { $notes "This word is used internally to wrap low-level code that does not do type-checking in safe user-visible words." } ; HELP: define-slot-word "( class slot word quot -- )" { $values { "class" "a class word" } { "slot" "a non-negative integer" } { "word" "a new word" } { "quot" "a quotation" } } { $description "Defines " { $snippet "word" } " to be a simple type-checking generic word that receives the slot number on the stack as a fixnum." } $low-level-note ; HELP: define-slots "( class spec -- )" { $values { "class" "a class word" } { "spec" "a sequence of triples" } } { $description "Defines a set of slot accessor/mutator words." $terpri "Each entry in the " { $snippet "spec" } " sequence is a three-element sequence with the following elements:" { $list "a slot number" { "a reader word, or " { $link f } } { "a writer word, or " { $link f } } } "If the reader or writer is " { $link f } ", the corresponding word is not defined." } $low-level-note ; HELP: simple-slots "( class slots base -- spec )" { $values { "class" "a class word" } { "slots" "a sequence of strings" } { "base" "a slot number" } } { $description "Constructs a slot specification for " { $link define-slots } " where each slot is named by an element of " { $snippet "slots" } " prefixed by the name of the class. Slots are numbered consecutively starting from " { $snippet "base" } ". Reader and writer words are defined in the current vocabulary, with the reader word having the same name as the slot, and the writer word name prefixed by " { $snippet "\"set-\"" } "." } ;