matcher: clean up unclear vars situaton.

With this commit, the new broken test case passes.

The main issue is not clearly separating temporary variables
in mach-guards from public variables.

* share/txr/stdlib/match.tl (match-vars): Remove pure-vars and
pure-var-exprs from this inheritance base, as well as the
related lets method.
(match-guard): Add the "pure" slots here, under new names:
pure-temps and pure-temp-exprs. This renaming is for clarity.
Add the lets method here, based on these new variables.
Add new slots temps, representing the impure temps.
There is no temp-exprs because impure temps are bound
to nil and later assigned.
(compiled-match get-temps): Method removed.
(compiled-match get-vars): Rewritten to avoid using get-temps
which doesn't exist any more. This method has a clear purpose:
to all the public variables coming from the patterns themselves,
whether those variables are promoted into a guard-chain for
early binding or whether they are attached on the
compiled-match object.
(compiled-match wrap-guards): Ensure that the new temps
from the guard-chain objects are bound with let.
(compile-struct-match, compile-vec-match,
compile-range-match, compile-dwim-predicate-match,
compile-cons-structure, compile-hash-match): pure-vars rename.
(compile-loop-match): We no longer bind cm.(get-temps) here.
That method doesn't exist. If we are not doing @(some), we
bind cm-vars: the public vars collected from cm. We need
local copies of them to catch their values and accumulate them
into list. In the match-guard constructor, we move the
collect-gens into temps; they are not public variables.
(compile-parallel-match): Drop ^(let ,pm.(get-temps) ...) from
the expansion.

0 files changed, 0 insertions, 0 deletions