+
+HELP: BUILTIN:
+{ $syntax "BUILTIN: class slots ... ;" }
+{ $values { "class" "a builtin class" } { "definition" "a word definition" } }
+{ $description "A representation of a builtin class from the VM. This word cannot define new builtins but is meant to provide a paper trail to which vocabularies define the builtins. To define new builtins requires adding them to the VM." } ;
+
+HELP: PRIMITIVE:
+{ $syntax "PRIMITIVE: word ( stack -- effect )" }
+{ $description "A reference to a primitive word of from the VM. This word cannot define new primitives but is meant to provide a paper trail to which vocabularies define the primitives. To define new primitves requires adding them to the VM." } ;
+
+HELP: MEMO:
+{ $syntax "MEMO: word ( stack -- effect ) definition... ;" }
+{ $values { "word" "a new word to define" } { "definition" "a word definition" } }
+{ $description "Defines the given word at parse time as one which memoizes its output given a particular input. The stack effect is mandatory." } ;
+
+HELP: IDENTITY-MEMO:
+{ $syntax "IDENTITY-MEMO: word ( stack -- effect ) definition... ;" }
+{ $values { "word" "a new word to define" } { "definition" "a word definition" } }
+{ $description "Defines the given word at parse time as one which memoizes its output given a particular input which is identical to another input. The stack effect is mandatory." } ;
+
+HELP: IDENTITY-MEMO::
+{ $syntax "IDENTITY-MEMO:: word ( stack -- effect ) definition... ;" }
+{ $values { "word" "a new word to define" } { "definition" "a word definition" } }
+{ $description "Defines the given word at parse time as one which memoizes its output given a particular input with locals which is identical to another input. The stack effect is mandatory." } ;