Remove weird __tag_is form by adding a T_LITSYM type and using = operator.

Step towards having first class symbols...


git-svn-id: http://svn.drobilla.net/resp/resp@362 ad02d1e2-f140-0410-9f75-f8b11f17cedd

9 files changed, 30 insertions, 45 deletions

diff --git a/src/c.cpp b/src/c.cpp
index d139c35..66a4963 100644
--- a/src/c.cpp
+++ b/src/c.cpp
@@ -52,7 +52,6 @@ struct CEngine : public Engine {
 	CVal    compileGlobalSet(CEnv& cenv, const string& s, CVal v, const AST* t);
 	CVal    compileGlobalGet(CEnv& cenv, const string& s, CVal v);
 	CVal    compileIf(CEnv& cenv, const AST* cond, const AST* then, const AST* aelse);
-	CVal    compileIsA(CEnv& cenv, CVal rtti, CVal tag);
 	CVal    compileLiteral(CEnv& cenv, const AST* lit);
 	CVal    compilePrimitive(CEnv& cenv, const ATuple* prim);
 	CVal    compileString(CEnv& cenv, const char* str);
@@ -265,12 +264,6 @@ CEngine::compileIf(CEnv& cenv, const ATuple* aif)
 #endif
 
 CVal
-CEngine::compileIsA(CEnv& cenv, CVal rtti, CVal tag)
-{
-	return NULL;
-}
-
-CVal
 CEngine::compilePrimitive(CEnv& cenv, const ATuple* prim)
 {
 	ATuple::const_iterator i = prim->begin();
diff --git a/src/compile.cpp b/src/compile.cpp
index 4fed182..393084e 100644
--- a/src/compile.cpp
+++ b/src/compile.cpp
@@ -37,18 +37,23 @@ compile_symbol(CEnv& cenv, const ASymbol* sym) throw()
 }
 
 static CVal
-compile_type(CEnv& cenv, const AST* type) throw()
+compile_literal_symbol(CEnv& cenv, const ASymbol* sym) throw()
 {
-	const ASymbol* sym      = type->as_tuple()->head()->as_symbol();
-	CVal*          existing = cenv.vals.ref(sym);
+	CVal* existing = cenv.vals.ref(sym);
 	if (existing) {
 		return *existing;
 	} else {
-		CVal compiled = cenv.engine()->compileString(
-			cenv, (string("__T_") + type->as_tuple()->head()->str()).c_str());
+		CVal compiled = cenv.engine()->compileString(cenv, (string("__T_") + sym->sym()).c_str());
 		cenv.vals.def(sym, compiled);
 		return compiled;
 	}
+
+}
+
+static CVal
+compile_type(CEnv& cenv, const AST* type) throw()
+{
+	return compile_literal_symbol(cenv, type->as_tuple()->head()->as_symbol());
 }
 
 static CVal
@@ -142,16 +147,6 @@ compile_if(CEnv& cenv, const ATuple* aif) throw()
 }
 
 static CVal
-compile_tag_is(CEnv& cenv, const ATuple* call) throw()
-{
-	const AST*     lhs  = call->list_ref(1);
-	const ASymbol* tag  = call->list_ref(2)->as_symbol();
-	const ATuple*  patT = new ATuple(tag, 0, Cursor());
-
-	return cenv.engine()->compileIsA(cenv, resp_compile(cenv, lhs), compile_type(cenv, patT));
-}
-
-static CVal
 compile_call(CEnv& cenv, const ATuple* call) throw()
 {
 	CFunc f = resp_compile(cenv, call->head());
@@ -181,6 +176,8 @@ resp_compile(CEnv& cenv, const AST* ast) throw()
 		return cenv.engine()->compileString(cenv, ((AString*)ast)->cppstr.c_str());
 	case T_SYMBOL:
 		return compile_symbol(cenv, ast->as_symbol());
+	case T_LITSYM:
+		return compile_literal_symbol(cenv, (ASymbol*)ast);
 	case T_TUPLE:
 	{
 		const ATuple* const  call = ast->as_tuple();
@@ -202,8 +199,6 @@ resp_compile(CEnv& cenv, const AST* ast) throw()
 			return compile_fn(cenv, call);
 		else if (form == "if")
 			return compile_if(cenv, call);
-		else if (form == "__tag_is")
-			return compile_tag_is(cenv, call);
 		else
 			return compile_call(cenv, call);
 	}
diff --git a/src/constrain.cpp b/src/constrain.cpp
index 39a0287..4bd6c08 100644
--- a/src/constrain.cpp
+++ b/src/constrain.cpp
@@ -394,6 +394,7 @@ resp_constrain(TEnv& tenv, Constraints& c, const AST* ast) throw(Error)
 		c.constrain(tenv, ast, tenv.named("String"));
 		break;
 	case T_SYMBOL:
+	case T_LITSYM:
 		constrain_symbol(tenv, c, ast->as_symbol());
 		break;
 	case T_TUPLE:
diff --git a/src/expand.cpp b/src/expand.cpp
index 020410e..eb508f1 100644
--- a/src/expand.cpp
+++ b/src/expand.cpp
@@ -113,7 +113,7 @@ initLang(PEnv& penv, TEnv& tenv)
 {
 	// Types
 	const char* types[] = {
-		"Bool", "Float", "Int",  "Nothing", "Quote", "String", 0 };
+		"Bool", "Float", "Int",  "Nothing", "Quote", "String", "Symbol", 0 };
 	for (const char** t = types; *t; ++t) {
 		const ASymbol* sym = penv.sym(*t);
 		tenv.def(sym, sym); // FIXME: define to NULL?
diff --git a/src/lift.cpp b/src/lift.cpp
index 222cd09..201d40f 100644
--- a/src/lift.cpp
+++ b/src/lift.cpp
@@ -271,8 +271,6 @@ resp_lift(CEnv& cenv, Code& code, const AST* ast) throw()
 			return lift_fn(cenv, code, call);
 		else if (form == "if")
 			return lift_args(cenv, code, call);
-		else if (form == "__tag_is")
-			return call;
 		else
 			return lift_call(cenv, code, call);
 	}
diff --git a/src/llvm.cpp b/src/llvm.cpp
index 6ef25bb..f6874d7 100644
--- a/src/llvm.cpp
+++ b/src/llvm.cpp
@@ -67,7 +67,6 @@ struct LLVMEngine : public Engine {
 	CVal    compileGlobalSet(CEnv& cenv, const string& s, CVal v, const AST* t);
 	CVal    compileGlobalGet(CEnv& cenv, const string& s, CVal v);
 	CVal    compileIf(CEnv& cenv, const AST* cond, const AST* then, const AST* aelse);
-	CVal    compileIsA(CEnv& cenv, CVal rtti, CVal tag);
 	CVal    compileLiteral(CEnv& cenv, const AST* lit);
 	CVal    compilePrimitive(CEnv& cenv, const ATuple* prim);
 	CVal    compileString(CEnv& cenv, const char* str);
@@ -365,15 +364,6 @@ LLVMEngine::compileIf(CEnv& cenv, const AST* cond, const AST* then, const AST* a
 }
 
 CVal
-LLVMEngine::compileIsA(CEnv& cenv, CVal rtti, CVal tag)
-{
-	LLVMEngine* engine = reinterpret_cast<LLVMEngine*>(cenv.engine());
-	Value*      typeV  = llVal(tag);
-
-	return engine->builder.CreateICmp(CmpInst::ICMP_EQ, llVal(rtti), typeV);
-}
-
-CVal
 LLVMEngine::compilePrimitive(CEnv& cenv, const ATuple* prim)
 {
 	ATuple::const_iterator i = prim->iter_at(1);
diff --git a/src/pprint.cpp b/src/pprint.cpp
index a932065..ca2ee92 100644
--- a/src/pprint.cpp
+++ b/src/pprint.cpp
@@ -186,6 +186,7 @@ print_to(ostream& out, const AST* ast, unsigned indent, CEnv* cenv, bool types)
 	case T_STRING:
 		return out << '"' << ((const AString*)ast)->cppstr << '"';
 	case T_SYMBOL:
+	case T_LITSYM:
 		return out << ((const ASymbol*)ast)->sym();
 	}
 
diff --git a/src/resp.hpp b/src/resp.hpp
index f6e65ea..3c949a0 100644
--- a/src/resp.hpp
+++ b/src/resp.hpp
@@ -89,8 +89,9 @@ enum Tag {
 	T_INT32   = 8,
 	T_STRING  = 10,
 	T_SYMBOL  = 12,
-	T_TUPLE   = 14,
-	T_TVAR    = 16
+	T_LITSYM  = 14,
+	T_TUPLE   = 16,
+	T_TVAR    = 18
 };
 
 /// Garbage collector
@@ -409,6 +410,7 @@ AST::operator==(const AST& rhs) const
 	case T_STRING:
 		return ((AString*)this)->cppstr == ((AString*)&rhs)->cppstr;
 	case T_SYMBOL:
+	case T_LITSYM:
 		return ((ASymbol*)this)->sym() == ((ASymbol*)&rhs)->sym(); // interned
 	case T_UNKNOWN:
 		return this == &rhs;
@@ -658,7 +660,6 @@ struct Engine {
 	virtual CVal compileGlobalSet(CEnv& cenv, const string& s, CVal v, const AST* t)       = 0;
 	virtual CVal compileGlobalGet(CEnv& cenv, const string& s, CVal v)                     = 0;
 	virtual CVal compileIf(CEnv& cenv, const AST* cond, const AST* then, const AST* aelse) = 0;
-	virtual CVal compileIsA(CEnv& cenv, CVal rtti, CVal tag)                               = 0;
 	virtual CVal compileLiteral(CEnv& cenv, const AST* lit)                                = 0;
 	virtual CVal compilePrimitive(CEnv& cenv, const ATuple* prim)                          = 0;
 	virtual CVal compileString(CEnv& cenv, const char* str)                                = 0;
@@ -721,7 +722,7 @@ struct CEnv {
 		return rec ? *rec : ast;
 	}
 	void setType(const AST* ast, const AST* type) {
-		assert(!ast->to_symbol());
+		//assert(!ast->to_symbol());
 		const AST* tvar = tenv.var();
 		tenv.vars.insert(make_pair(ast, tvar));
 		tsubst.add(tvar, type);
diff --git a/src/simplify.cpp b/src/simplify.cpp
index 715202a..397c2b7 100644
--- a/src/simplify.cpp
+++ b/src/simplify.cpp
@@ -63,10 +63,10 @@ simplify_match(CEnv& cenv, const ATuple* match) throw()
 	tval.push_back(resp_simplify(cenv, match->list_ref(1)));
 	tval.push_back(new ALiteral<int32_t>(T_INT32, -1, Cursor()));
 
-	const ASymbol* tsym = cenv.penv.gensym("_matchT");
+	const ASymbol* tsym = cenv.penv.gensym("__tag");
 
 	List def(match->loc, cenv.penv.sym("def"), tsym, tval.head, NULL);
-	cenv.setType(tval.head, cenv.tenv.named("String"));
+	cenv.setType(tval.head, cenv.tenv.named("Symbol"));
 	
 	List copyIf;
 	copyIf.push_back(cenv.penv.sym("if"));
@@ -74,10 +74,16 @@ simplify_match(CEnv& cenv, const ATuple* match) throw()
 		const ATuple* pat  = (*i++)->as_tuple();
 		const AST*    body = *i++;
 
+		const ASymbol* consTag = cenv.penv.sym(pat->head()->str(), pat->head()->loc);
+		const_cast<ASymbol*>(consTag)->tag(T_LITSYM);
+		cenv.setType(consTag, cenv.tenv.named("Symbol"));
+
 		List cond;
-		cond.push_back(cenv.penv.sym("__tag_is"));
+		cond.push_back(cenv.penv.sym("="));
 		cond.push_back(tsym);
-		cond.push_back(pat->head());
+		cond.push_back(consTag);
+
+		cenv.setType(cond, cenv.tenv.named("Bool"));
 
 		copyIf.push_back(cond);
 		copyIf.push_back(resp_simplify(cenv, body));