Add support for existential type recovery.

	* interp/compiler.boot (compRecoverDomain): New.  Split from
	compRecoverGuard.
	(compRecoverGuard): Split.  Handle existential type recovery.
	(compScheme): New.  Register as compiler.
	* interp/g-opt.boot (optLET*): New.  Turn into LET-form if
	appropriate.  Register as backend transformer.
	* interp/fnewmeta.lisp (|PARSE-Scheme|): New.
	(|PARSE-Quantifier|): Likewise.
	(|PARSE-QuantifiedVariableList|): Likewise.
	(|PARSE-QuantifiedVariable|): Likewise.
	* interp/metalex.lisp (KEYWORDS): Add 'forall' and 'exist' as new
	keywords. 
	* interp/newaux.lisp: Register parser for expression schemes.
	* algebra/any.spad.pamphlet (=$Any): If the underlying domain has
	BasicType, use that equality operator.
	(coerce$Any): If the underlying domain has CoercibleTo OutputForm
	then use it.

1 files changed, 10 insertions, 0 deletions

diff --git a/src/interp/g-opt.boot b/src/interp/g-opt.boot
index c51987dc..0fb44255 100644
--- a/src/interp/g-opt.boot
+++ b/src/interp/g-opt.boot
@@ -492,6 +492,15 @@ optLET u ==
     rplac(rest def, second def)
   SUBLIS(inits,body)
 
+optLET_* form ==
+  form isnt ["LET*",:.] => form
+  ok := true
+  while ok for [[var,.],:inits] in tails second form repeat
+    if CONTAINED(var,inits) then ok := false
+  not ok => form
+  rplac(first form,"LET")
+  optLET form
+
 lispize x == first optimize [x]
  
 --% optimizer hash table
@@ -499,6 +508,7 @@ lispize x == first optimize [x]
 for x in '( (call         optCall) _
            (SEQ          optSEQ)_
            (LET          optLET)_
+           (LET_*        optLET_*)_
            (MINUS        optMINUS)_
            (QSMINUS      optQSMINUS)_
            (_-           opt_-)_