public object Visit(ParameterExpression parameter)
{
return(new XsParameter(parameter.Name, ctx.GetClrType(parameter.Type)));
}
private object ArithmethicOperation(BinaryExpression binaryOp, OpCode op, XzaarType resultType = null)
{
if (resultType == null)
{
resultType = XzaarBaseTypes.Number;
}
var il = ctx.GetILGenerator();
if (resultType.Name == "string")
{
// determine which side is a string
var leftType = binaryOp.Left.Type;
var rightType = binaryOp.Right.Type;
var boxLeft = false;
var boxRight = false;
// if both are strings, we can just find the normal string,string concat function and call that one.
// if one of the types are a valuetype (not a class or 'any'), then that type needs to be boxed
// then use the object,object concat function instead
MethodInfo targetConcatMethod = typeof(string).GetMethod("Concat", new[] { typeof(object), typeof(object) });
if (leftType.Name == "string")
{
if (rightType.Name == "string")
{
targetConcatMethod = typeof(string).GetMethod("Concat", new[] { typeof(string), typeof(string) });
}
else
{
#warning Concating string requires struct's to be boxed. TODO: Add boxing for structs!
boxRight = rightType.IsNumeric;
// numbers and structs needs to be boxed, right now we don't know if one is a struct or not
// check if boxing is necessary on the 'right' type.
}
}
else
{
boxLeft = leftType.IsNumeric;
// check if boxing is necessary on the 'left' type.
}
var l = Visit(binaryOp.Left);
TryLoadReference(l, il);
if (boxLeft)
{
il.Box(ctx.GetClrType(leftType));
}
var r = Visit(binaryOp.Right);
TryLoadReference(r, il);
if (boxRight)
{
il.Box(ctx.GetClrType(rightType));
}
il.Call(targetConcatMethod);
return(true);
}
// NOTE: arithmetic operations does NOT necessarily have to introduce a
// temporary variable, but COULD. I decided to skip it for simplicity
var left = Visit(binaryOp.Left);
TryLoadReference(left, il);
// if its not any of the ones above, it must be either a function call or constant
var right = Visit(binaryOp.Right);
TryLoadReference(right, il);
il.Emit(op);
return(true);
}
