PatternMatchAssertions

expr.spad line 1050 [edit on github]

Attaching assertions to symbols for pattern matching. Date Created: 21 Mar 1989

constant: Symbol -> Expression Integer

constant(x) tells the pattern matcher that x should match only the symbol 'x and no other quantity.

multiple: Symbol -> Expression Integer

multiple(x) tells the pattern matcher that x should preferably match a multi-term quantity in a sum or product. For matching on lists, multiple(x) tells the pattern matcher that x should match a list instead of an element of a list.

optional: Symbol -> Expression Integer

optional(x) tells the pattern matcher that x can match an identity (0 in a sum, 1 in a product or exponentiation).