BETA_TAC : tactic

SYNOPSIS

Beta-reduces all the beta-redexes in the conclusion of a goal.

DESCRIPTION

When applied to a goal A ?- t, the tactic BETA_TAC produces a new goal which results from beta-reducing all beta-redexes, at any depth, in t. Variables are renamed where necessary to avoid free variable capture.

    A ?- ...((\x. s1) s2)...
   ==========================  BETA_TAC
     A ?- ...(s1[s2/x])...

FAILURE CONDITIONS

Never fails, but will have no effect if there are no beta-redexes.

COMMENTS

Beta-reduction, and indeed, generalized beta reduction (GEN_BETA_CONV) are already among the basic rewrites, so happen anyway simply on REWRITE_TAC[]. But occasionally it is convenient to be able to invoke them separately.

SEE ALSO

BETA_CONV, BETA_RULE, GEN_BETA_CONV.