Clifford Wolf:

	Another cleanup in expression handling



git-svn-id: http://svn.clifford.at/openscad/trunk@43 b57f626f-c46c-0410-a088-ec61d464b74c

1 files changed, 105 insertions, 92 deletions

diff --git a/expr.cc b/expr.cc
index cefa3b9..f0e45d7 100644
--- a/expr.cc
+++ b/expr.cc
@@ -22,7 +22,6 @@
 
 Expression::Expression()
 {
-	type = 0;
 	const_value = NULL;
 }
 
@@ -36,124 +35,138 @@ Expression::~Expression()
 
 Value Expression::evaluate(const Context *context) const
 {
-	switch (type)
-	{
-	case '*':
+	if (type == "!")
+		return ! children[0]->evaluate(context);
+	if (type == "&&")
+		return children[0]->evaluate(context) && children[1]->evaluate(context);
+	if (type == "||")
+		return children[0]->evaluate(context) || children[1]->evaluate(context);
+	if (type == "*")
 		return children[0]->evaluate(context) * children[1]->evaluate(context);
-	case '/':
+	if (type == "/")
 		return children[0]->evaluate(context) / children[1]->evaluate(context);
-	case '%':
+	if (type == "%")
 		return children[0]->evaluate(context) % children[1]->evaluate(context);
-	case '+':
+	if (type == "+")
 		return children[0]->evaluate(context) + children[1]->evaluate(context);
-	case '-':
+	if (type == "-")
 		return children[0]->evaluate(context) - children[1]->evaluate(context);
-	case '?':
-		{
-			Value v = children[0]->evaluate(context);
-			if (v.type == Value::BOOL)
-				return children[v.b ? 1 : 2]->evaluate(context);
-			return Value();
+	if (type == "<")
+		return children[0]->evaluate(context) < children[1]->evaluate(context);
+	if (type == "<=")
+		return children[0]->evaluate(context) <= children[1]->evaluate(context);
+	if (type == "==")
+		return children[0]->evaluate(context) == children[1]->evaluate(context);
+	if (type == "!=")
+		return children[0]->evaluate(context) != children[1]->evaluate(context);
+	if (type == ">=")
+		return children[0]->evaluate(context) >= children[1]->evaluate(context);
+	if (type == ">")
+		return children[0]->evaluate(context) > children[1]->evaluate(context);
+	if (type == "?:") {
+		Value v = children[0]->evaluate(context);
+		if (v.type == Value::BOOL)
+			return children[v.b ? 1 : 2]->evaluate(context);
+		return Value();
+	}
+	if (type == "[]") {
+		Value v1 = children[0]->evaluate(context);
+		Value v2 = children[1]->evaluate(context);
+		if (v1.type == Value::VECTOR && v2.type == Value::NUMBER) {
+			int i = v2.num;
+			if (i < v1.vec.size())
+				return *v1.vec[i];
 		}
-	case 'I':
+		return Value();
+	}
+	if (type == "I")
 		return children[0]->evaluate(context).inv();
-	case 'C':
+	if (type == "C")
 		return *const_value;
-	case 'R':
-		{
-			Value v1 = children[0]->evaluate(context);
-			Value v2 = children[1]->evaluate(context);
-			Value v3 = children[2]->evaluate(context);
-			if (v1.type == Value::NUMBER && v2.type == Value::NUMBER && v3.type == Value::NUMBER) {
-				Value r = Value();
-				r.type = Value::RANGE;
-				r.range_begin = v1.num;
-				r.range_step = v2.num;
-				r.range_end = v3.num;
-				return r;
-			}
-			return Value();
+	if (type == "R") {
+		Value v1 = children[0]->evaluate(context);
+		Value v2 = children[1]->evaluate(context);
+		Value v3 = children[2]->evaluate(context);
+		if (v1.type == Value::NUMBER && v2.type == Value::NUMBER && v3.type == Value::NUMBER) {
+			Value r = Value();
+			r.type = Value::RANGE;
+			r.range_begin = v1.num;
+			r.range_step = v2.num;
+			r.range_end = v3.num;
+			return r;
 		}
-	case 'V':
-		{
-			Value v;
-			v.type = Value::VECTOR;
-			for (int i = 0; i < children.size(); i++)
-				v.vec.append(new Value(children[i]->evaluate(context)));
-			return v;
-		}
-	case 'L':
+		return Value();
+	}
+	if (type == "V") {
+		Value v;
+		v.type = Value::VECTOR;
+		for (int i = 0; i < children.size(); i++)
+			v.vec.append(new Value(children[i]->evaluate(context)));
+		return v;
+	}
+	if (type == "L")
 		return context->lookup_variable(var_name);
-	case 'N':
-		{
-			Value v = children[0]->evaluate(context);
+	if (type == "N")
+	{
+		Value v = children[0]->evaluate(context);
 
-			if (v.type == Value::VECTOR && var_name == QString("x"))
-				return *v.vec[0];
-			if (v.type == Value::VECTOR && var_name == QString("y"))
-				return *v.vec[1];
-			if (v.type == Value::VECTOR && var_name == QString("z"))
-				return *v.vec[2];
+		if (v.type == Value::VECTOR && var_name == QString("x"))
+			return *v.vec[0];
+		if (v.type == Value::VECTOR && var_name == QString("y"))
+			return *v.vec[1];
+		if (v.type == Value::VECTOR && var_name == QString("z"))
+			return *v.vec[2];
 
-			if (v.type == Value::RANGE && var_name == QString("begin"))
-				return Value(v.range_begin);
-			if (v.type == Value::RANGE && var_name == QString("step"))
-				return Value(v.range_step);
-			if (v.type == Value::RANGE && var_name == QString("end"))
-				return Value(v.range_end);
+		if (v.type == Value::RANGE && var_name == QString("begin"))
+			return Value(v.range_begin);
+		if (v.type == Value::RANGE && var_name == QString("step"))
+			return Value(v.range_step);
+		if (v.type == Value::RANGE && var_name == QString("end"))
+			return Value(v.range_end);
 
-			return Value();
-		}
-	case 'F':
-		{
-			QVector<Value> argvalues;
-			for (int i=0; i < children.size(); i++)
-				argvalues.append(children[i]->evaluate(context));
-			return context->evaluate_function(call_funcname, call_argnames, argvalues);
-		}
-	default:
-		abort();
+		return Value();
 	}
+	if (type == "F") {
+		QVector<Value> argvalues;
+		for (int i=0; i < children.size(); i++)
+			argvalues.append(children[i]->evaluate(context));
+		return context->evaluate_function(call_funcname, call_argnames, argvalues);
+	}
+	abort();
 }
 
 QString Expression::dump() const
 {
-	switch (type)
-	{
-	case '*':
-	case '/':
-	case '%':
-	case '+':
-	case '-':
+	if (type == "*" || type == "/" || type == "%" || type == "+" || type == "-" ||
+			type == "<" || type == "<=" || type == "==" || type == "!=" || type == ">=" || type == ">")
 		return QString("(%1 %2 %3)").arg(children[0]->dump(), QString(type), children[1]->dump());
-	case '?':
+	if (type == "?:")
 		return QString("(%1 ? %2 : %3)").arg(children[0]->dump(), children[1]->dump(), children[2]->dump());
-	case 'I':
+	if (type == "[]")
+		return QString("(%1[%2])").arg(children[0]->dump(), children[1]->dump());
+	if (type == "I")
 		return QString("(-%1)").arg(children[0]->dump());
-	case 'C':
+	if (type == "C")
 		return const_value->dump();
-	case 'R':
+	if (type == "R")
 		return QString("[%1 : %2 : %3]").arg(children[0]->dump(), children[1]->dump(), children[2]->dump());
-	case 'V':
+	if (type == "V")
 		return QString("[%1, %2, %3]").arg(children[0]->dump(), children[1]->dump(), children[2]->dump());
-	case 'L':
+	if (type == "L")
 		return var_name;
-	case 'N':
+	if (type == "N")
 		return QString("(%1.%2)").arg(children[0]->dump(), var_name);
-	case 'F':
-		{
-			QString text = call_funcname + QString("(");
-			for (int i=0; i < children.size(); i++) {
-				if (i > 0)
-					text += QString(", ");
-				if (!call_argnames[i].isEmpty())
-					text += call_argnames[i] + QString(" = ");
-				text += children[i]->dump();
-			}
-			return text + QString(")");
+	if (type == "F") {
+		QString text = call_funcname + QString("(");
+		for (int i=0; i < children.size(); i++) {
+			if (i > 0)
+				text += QString(", ");
+			if (!call_argnames[i].isEmpty())
+				text += call_argnames[i] + QString(" = ");
+			text += children[i]->dump();
 		}
-	default:
-		abort();
+		return text + QString(")");
 	}
+	abort();
 }