Q.MATCH_RENAME

STRUCTURE

SYNOPSIS

Replaces selected terms with new variables by matching a pattern against the goal statement.

DESCRIPTION

When applied to the goal (asl, w), the tactic Q.MATCH_RENAME_TAC q ls parses the quotation q in the context of the goal, producing a term to use as a pattern. The tactic then attempts a (first order) match of the pattern against the term w.

For each variable v in the pattern, there will be an instantiation term t, such that the substitution pattern[v1 |-> t1, v2 |-> t2, ...] produces w. The effect of the tactic is to then replace each t with the corresponding v, yielding a new goal. The list ls is of exceptions: if a variable v’s name appears in ls, then no replacement of v for t is made.

FAILURE

MATCH_RENAME_TAC fails if the pattern provided does not match the goal, or if variables from the goal are used in the pattern in ways that make the pattern fail to type-check.

EXAMPLE

If the current goal is

   ?- (f x = Pair C'' C0') ==> (f C'' = f C0')

then applying the tactic Q.MATCH_RENAME_TAC `(f x = Pair c1 c2) ==> X` ["X"] results in the goal

   ?- (f x = Pair c1 c2) ==> (f c1 = f c2)

COMMENTS

This tactic is equivalent to first applying Q.MATCH_ABBREV_TAC q, then applying Q.RM_ABBREV_TAC `v` for each v in q whose name is not in ls.

SEEALSO

MATCH_ABBREV_TAC, MATCH_ASSUM_RENAME_TAC