pcase--u

pcase--u is a compiled Lisp function in `pcase.el'.

(pcase--u BRANCHES)

Expand matcher for rules BRANCHES.
Each BRANCH has the form (MATCH CODE . VARS) where
CODE is the code generator for that branch.
VARS is the set of vars already bound by earlier matches.
MATCH is the pattern that needs to be matched, of the form:
(match VAR . UPAT)
(and MATCH ...)
(or MATCH ...)