Don't use strings to identify vars, use numbers

1 files changed, 13 insertions, 93 deletions

diff --git a/builtins.c b/builtins.c
index 0256699..7d32d98 100644
--- a/builtins.c
+++ b/builtins.c
@@ -374,12 +374,7 @@ compareterms(Term *t1, Term *t2)
 		/* Same type term */
 		switch(t1->tag){
 		case VariableTerm:
-			if(runestrcmp(t1->text, L"_") == 0 && runestrcmp(t2->text, L"_") == 0)
-				result = 1; /* Special case since _ and _ are always different */
-			else if(t1->clausenr == t2->clausenr)
-				result = runestrcmp(t1->text, t2->text);
-			else
-				result = Compare(t1->clausenr, t2->clausenr);
+			result = Compare(t1->varnr, t2->varnr);
 			break;
 		case FloatTerm:
 			result = Compare(t1->dval, t2->dval);
@@ -465,7 +460,7 @@ builtinfunctor(Term *goal, Binding **bindings, Module *module)
 			int i;
 			Term *args = nil;
 			for(i = 0; i < arity->ival; i++){
-				Term *arg = mkvariable(L"_");
+				Term *arg = mkvariable();
 				args = appendterm(args, arg);
 			}
 			Term *realterm = mkcompound(name->text, arity->ival, args);
@@ -823,77 +818,10 @@ builtinsetoutput(Term *goal, Binding **bindings, Module *module)
 	return 1;
 }
 
-Term *
-readtermvars(Term *t)
-{
-	Term *vars;
-	switch(t->tag){
-	case VariableTerm:
-		vars = copyterm(t, nil);
-		break;
-	case CompoundTerm:
-		vars = nil;
-		int n = t->arity;
-		for(t = t->children; n > 0; t = t->next, n--){
-			Term *childvars = readtermvars(t);
-			while(childvars){
-				Term *childvarscopy = copyterm(childvars, nil);
-				vars = appendterm(vars, childvarscopy);
-				childvars = childvars->next;
-			}
-		}
-		break;
-	default:
-		vars = nil;
-	}
-	return vars;
-}
-
-Term *
-varsandnames(Term *vars)
-{
-	Term *varsnames = nil;
-	Term *var;
-	for(var = vars; var != nil; var = var->next){
-		if(runestrcmp(var->text, L"_") == 0)
-			continue;
-		Term *varname = mkatom(var->text);
-		varname->next = copyterm(var, nil);
-		Term *pair = mkcompound(L"=", 2, varname);
-		varsnames = appendterm(varsnames, pair);
-	}
-	return varsnames;
-}
-
-Term *
-singletons(Term *vars)
-{
-	Term *var;
-	Term *varsnames = varsandnames(vars);
-	Term *singles = nil;
-
-	for(var = varsnames; var != nil; var = var->next){
-		Term *tmp;
-		int duplicate = 0;
-		for(tmp = varsnames; tmp != nil ; tmp = tmp->next){
-			if(tmp == var)
-				continue;
-			if(runestrcmp(var->children->text, tmp->children->text) == 0){
-				duplicate = 1;
-				break;
-			}
-		}
-		if(!duplicate)
-			singles = appendterm(singles, copyterm(var, nil));
-	}
-	return singles;
-}
-
 int
 builtinreadterm(Term *goal, Binding **bindings, Module *module)
 {
 	USED(bindings);
-
 	Term *stream = goal->children;
 	Term *term = stream->next;
 	Term *options = term->next;
@@ -910,7 +838,8 @@ builtinreadterm(Term *goal, Binding **bindings, Module *module)
 		Throw(permissionerror(L"input", L"binary_stream", stream));
 
 	Term *realterm;
-	int error = readterm(stream, &realterm, module);
+	VarName *varnames;
+	int error = readterm(stream, &realterm, module, &varnames);
 	if(error)
 		Throw(realterm);
 
@@ -921,25 +850,16 @@ builtinreadterm(Term *goal, Binding **bindings, Module *module)
 	Term *uniquevars = nil;
 	Term *varsnames = nil;
 	if(options->tag == CompoundTerm){
-		Term *allvars = readtermvars(realterm);
-		Term *tmp1;
-		for(tmp1 = allvars; tmp1 != nil; tmp1 = tmp1->next){
-			Term *tmp2;
-			int duplicate = 0;
-			for(tmp2 = uniquevars; tmp2 != nil; tmp2 = tmp2->next){
-				if(runestrcmp(tmp2->text, tmp1->text) == 0){
-					duplicate = 1;
-					break;
-				}
-			}
-			if(!duplicate){
-				Term *v = copyterm(tmp1, nil);
-				uniquevars = appendterm(uniquevars, v);
-			}
+		VarName *vn;
+		for(vn = varnames; vn != nil; vn = vn->next){
+			uniquevars = appendterm(uniquevars, copyterm(vn->var, nil));
+			Term *name = mkatom(vn->name);
+			name->next = copyterm(vn->var, nil);
+			Term *vnpair = mkcompound(L"=", 2, name);
+			varsnames = appendterm(varsnames, vnpair);
+			if(vn->count == 1)
+				singlevars = appendterm(singlevars, copyterm(vnpair, nil));
 		}
-
-		varsnames = varsandnames(uniquevars);
-		singlevars = singletons(allvars);
 	}
 
 	Term *op;