public static ArraySegment <AphidMacro> Parse(List <AphidExpression> ast)
{
var macros = new AphidMacro[ast.Count];
var macroCount = 0;
for (var i = 0; i < ast.Count; i++)
{
var node = ast[i];
BinaryOperatorExpression binOp;
CallExpression call;
if (node.Type == AphidExpressionType.BinaryOperatorExpression &&
((binOp = (BinaryOperatorExpression)node).LeftOperand.Type ==
AphidExpressionType.IdentifierExpression) &&
binOp.RightOperand.Type == AphidExpressionType.CallExpression &&
(call = (CallExpression)binOp.RightOperand).FunctionExpression.Type ==
AphidExpressionType.IdentifierExpression &&
((IdentifierExpression)call.FunctionExpression).Identifier == "macro" &&
call.Args.Count == 1 &&
call.Args[0].Type == AphidExpressionType.FunctionExpression)
{
macros[macroCount++] = new AphidMacro(
((IdentifierExpression)binOp.LeftOperand).Identifier,
(FunctionExpression)call.Args[0],
binOp);
}
}
return(new ArraySegment <AphidMacro>(macros, 0, macroCount));
}
protected override List <AphidExpression> OnMutate(List <AphidExpression> ast)
{
var macros = AphidMacro.Parse(ast);
for (var i = 0; i < macros.Count; i++)
{
var m = macros.Array[i];
if (_macros.ContainsKey(m.Name))
{
throw new AphidParserException(
"Macro with name '{0}' already exists.",
m.Name);
}
_macros.Add(m.Name, m);
}
var filtered = new List <AphidExpression>(ast.Count);
for (var i = 0; i < ast.Count; i++)
{
var node = ast[i];
var include = true;
for (var j = 0; j < macros.Count; j++)
{
if (node == macros.Array[j].OriginalExpression)
{
include = false;
break;
}
}
if (include)
{
filtered.Add(node);
}
}
return(filtered);
}
private AphidMacro GetMacro(CallExpression call, AphidMacro[] macros)
{
var idExp = call.FunctionExpression as IdentifierExpression;
if (idExp == null)
{
return null;
}
return macros.SingleOrDefault(x => x.Name == idExp.Identifier);
}