Restrict loop variable scopes, take 2.

	* interp/iterator.boot (compReduce1): Maintain proper scope for
	loop variables.
	(compRepeatOrCollect): Really maintain proper scope for loop variables.
	* interp/compiler.boot (eltModemapFilter): Highlight faulty selector.
	(seteltModemapFilter): Likewise.
	* interp/c-util.boot (stackMessage): Don't build message if there
	is no argument for substitution.
	* algebra/aggcat.spad.pamphlet (#$UnaryRecursiveAggregate):
	Declare free loop variable.
	(cycleEntry$UnaryRecursiveAggregate): Likewise.
	(cycleLength): Likewise.
	(merge$OneDimensionalArrayAggregate): Likewise.
	(delete$OneDimensionalArrayAggregate): Likewise.
	(position$ListAggregate): Likewise.
	* algebra/array1.spad.pamphlet (merge!$IndexedFlexibleArray): Likewise.
	* algebra/combfunc.spad.pamphlet (K2fact$CombinatorialFunction):
	Likewise. 
	* algebra/curve.spad.pamphlet
	(nonSingularModel$FunctionFieldCategory):  Likewise.
	* algebra/dpolcat.spad.pamphlet
	(differentiate$DifferentialPolynomialCategory): Likewise.
	* algebra/efstruc.spad.pamphlet
	(validExponential$ElementaryFunctionStructurePackage):  Likewise.
	(ker2explogs$InnerTrigonometricManipulations): Likewise.
	(complexNormalize$TrigonometricManipulations): Likewise.

3 files changed, 16 insertions, 12 deletions

diff --git a/src/interp/c-util.boot b/src/interp/c-util.boot
index a8475327..a2691741 100644
--- a/src/interp/c-util.boot
+++ b/src/interp/c-util.boot
@@ -512,7 +512,9 @@ unStackWarning(msg,args) ==
   nil
  
 stackMessage(msg,args == nil) ==
-  $compErrorMessageStack:= [buildMessage(msg,args),:$compErrorMessageStack]
+  if args ^= nil then
+    msg := buildMessage(msg,args)
+  $compErrorMessageStack:= [msg,:$compErrorMessageStack]
   nil
  
 stackMessageIfNone msg ==
diff --git a/src/interp/compiler.boot b/src/interp/compiler.boot
index b120fc9d..397e6b9a 100644
--- a/src/interp/compiler.boot
+++ b/src/interp/compiler.boot
@@ -563,7 +563,7 @@ eltModemapFilter(name,mmList,e) ==
   isConstantId(name,e) =>
     l:= [mm for mm in mmList | mm is [[.,.,.,sel,:.],:.] and sel=name] => l
             --there are elts with extra parameters
-    stackMessage('"selector variable: %1 is undeclared and unbound",[name])
+    stackMessage('"selector variable: %1b is undeclared and unbound",[name])
     nil
   mmList
 
@@ -571,7 +571,7 @@ seteltModemapFilter(name,mmList,e) ==
   isConstantId(name,e) =>
     l:= [mm for (mm:= [[.,.,.,sel,:.],:.]) in mmList | sel=name] => l
             --there are setelts with extra parameters
-    stackMessage('"selector variable: %1 is undeclared and unbound",[name])
+    stackMessage('"selector variable: %1b is undeclared and unbound",[name])
     nil
   mmList
 
@@ -727,7 +727,7 @@ setqMultiple(nameList,val,m,e) ==
           [[name,:mode] for [":",name,mode] in l]
         stackMessage('"no multiple assigns to mode: %1p",[t])
   #nameList^=#selectorModePairs =>
-    stackMessage('"%1 must decompose into %2 components",[val,#nameList])
+    stackMessage('"%1b must decompose into %2 components",[val,#nameList])
   3 --generate code; return
   assignList:=
     [([.,.,e]:= compSetq1(x,["elt",g,y],z,e) or return "failed").expr
@@ -737,7 +737,7 @@ setqMultiple(nameList,val,m,e) ==
 
 setqMultipleExplicit(nameList,valList,m,e) ==
   #nameList^=#valList =>
-    stackMessage('"Multiple assignment error; # of items in: %1 must = # in: %2",[nameList,valList])
+    stackMessage('"Multiple assignment error; # of items in: %1b must = # in: %2",[nameList,valList])
   gensymList:= [genVariable() for name in nameList]
   assignList:=
              --should be fixed to declare genVar when possible
diff --git a/src/interp/iterator.boot b/src/interp/iterator.boot
index d62f4939..19ead302 100644
--- a/src/interp/iterator.boot
+++ b/src/interp/iterator.boot
@@ -45,10 +45,11 @@ compReduce1(form is ["REDUCE",op,.,collectForm],m,e,$formalArgList) ==
   if STRINGP op then op:= INTERN op
   ^MEMQ(collectOp,'(COLLECT COLLECTV COLLECTVEC)) =>
         systemError ["illegal reduction form:",form]
-  $sideEffectsList: local
-  $until: local
-  $initList: local
-  $endTestList: local
+  $sideEffectsList: local := nil
+  $until: local := nil
+  $initList: local := nil
+  $endTestList: local := nil
+  oldEnv := e
   $e:= e
   itl:= [([.,$e]:= compIterator(x,$e) or return "failed").(0) for x in itl]
   itl="failed" => return nil
@@ -73,7 +74,7 @@ compReduce1(form is ["REDUCE",op,.,collectForm],m,e,$formalArgList) ==
   if $until then
     [untilCode,.,e]:= comp($until,$Boolean,e)
     finalCode:= substitute(["UNTIL",untilCode],'$until,finalCode)
-  [finalCode,m,e]
+  [finalCode,m,oldEnv]
 
 ++ returns the identity element of the `reduction' operation `x'
 ++ over a list -- a monoid homomorphism.   
@@ -93,6 +94,7 @@ compRepeatOrCollect(form,m,e) ==
     ,e) where
       fn(form,$exitModeStack,$leaveLevelStack,$formalArgList,e) ==
         $until: local
+        oldEnv := e
         [repeatOrCollect,:itl,body]:= form
         itl':=
           [([x',e]:= compIterator(x,e) or return "failed"; x') for x in itl]
@@ -135,7 +137,7 @@ compRepeatOrCollect(form,m,e) ==
         T := coerceExit([form',m'',e'],targetMode) or return nil
         -- iterator variables and other variables declared in
         -- in a loop are local to the loop.
-        [T.expr,T.mode,e]
+        [T.expr,T.mode,oldEnv]
  
 --constructByModemap([x,source,e],target) ==
 --  u:=
@@ -213,7 +215,7 @@ compIterator(it,e) ==
   it is ["WHILE",p] =>
     [p',m,e]:=
       comp(p,$Boolean,e) or return
-        stackMessage('"WHILE operand: %1 is not Boolean valued",[p])
+        stackMessage('"WHILE operand: %1b is not Boolean valued",[p])
     [["WHILE",p'],e]
   it is ["UNTIL",p] => ($until:= p; ['$until,e])
   it is ["|",x] =>