private bool ParseDeclaration(ref ASTNode node)
{
AttributeNode attrNode = null;
LightList <AttributeNode> attributes = LightList <AttributeNode> .Get();
while (ParseAttribute(ref attrNode))
{
attributes.Add(attrNode);
if (tokenStream.Current != ExpressionTokenType.ArrayAccessOpen)
{
break;
}
}
if (attributes.size == 0)
{
LightList <AttributeNode> .Release(ref attributes);
}
if (tokenStream.Current != ExpressionTokenType.Identifier)
{
return(false);
}
// modifiers? -> returnType -> name -> signature -> openBrace * closeBrace
tokenStream.Save();
bool isStatic = false;
if (tokenStream.Current == "static")
{
isStatic = true;
tokenStream.Advance();
}
ExpressionParser parser = new ExpressionParser(tokenStream);
StructList <LambdaArgument> signature = null;
TypeLookup typeLookup = default;
if (!parser.ParseTypePath(ref typeLookup))
{
goto fail;
}
tokenStream.Set(parser.GetTokenPosition());
parser.Release(false);
if (tokenStream.Current != ExpressionTokenType.Identifier)
{
goto fail;
}
string name = tokenStream.Current.value;
tokenStream.Advance();
// if semi colon then we have a field!
if (tokenStream.Current == ExpressionTokenType.SemiColon)
{
tokenStream.Advance();
node = new FieldNode()
{
name = name,
isStatic = isStatic,
attributes = attributes,
typeLookup = typeLookup
};
return(true);
}
if (tokenStream.Current != ExpressionTokenType.ParenOpen)
{
goto fail;
}
signature = StructList <LambdaArgument> .Get();
if (tokenStream.NextTokenIs(ExpressionTokenType.ParenClose))
{
tokenStream.Advance(2);
}
else
{
int matchingIndex = tokenStream.FindMatchingIndex(ExpressionTokenType.ParenOpen, ExpressionTokenType.ParenClose);
if (matchingIndex == -1)
{
goto fail;
}
TokenStream subStream = tokenStream.AdvanceAndReturnSubStream(matchingIndex);
subStream.Advance();
tokenStream.Advance();
if (!ExpressionParser.ParseSignature(subStream, signature))
{
goto fail;
}
for (int i = 0; i < signature.size; i++)
{
if (signature.array[i].type == null)
{
throw new ParseException($"When defining a method you must specify a type for all arguments. Found identifier {signature.array[i].identifier} but no type was given.");
}
}
}
if (tokenStream.Current != ExpressionTokenType.ExpressionOpen)
{
goto fail;
}
BlockNode block = ParseBlock();
node = new MethodNode()
{
body = block,
returnTypeLookup = typeLookup,
attributes = attributes,
name = name,
isStatic = isStatic,
signatureList = signature != null?signature.ToArray() : s_EmptySignature
};
StructList <LambdaArgument> .Release(ref signature);
parser.Release(false);
return(true);
fail:
{
tokenStream.Restore();
parser.Release(false);
typeLookup.Release();
signature?.Release();
return(false);
}
}
private bool ParseLocalVariableDeclaration(ref ASTNode node)
{
ExpressionParser parser = default;
TypeLookup typeLookup = default;
if (tokenStream.Current == ExpressionTokenType.Var)
{
if (!tokenStream.NextTokenIs(ExpressionTokenType.Identifier))
{
return(false);
}
tokenStream.Advance();
}
else if (tokenStream.Current == ExpressionTokenType.Identifier)
{
tokenStream.Save();
parser = new ExpressionParser(tokenStream);
if (!parser.ParseTypePath(ref typeLookup))
{
goto fail;
}
tokenStream.Set(parser.GetTokenPosition());
parser.Release(false);
}
else
{
goto fail;
}
if (tokenStream.Current != ExpressionTokenType.Identifier)
{
goto fail;
}
string name = tokenStream.Current.value;
tokenStream.Advance();
if (tokenStream.Current == ExpressionTokenType.SemiColon)
{
tokenStream.Advance();
node = new LocalVariableNode()
{
name = name,
typeLookup = typeLookup // will be default for var
};
return(true);
}
if (tokenStream.Current == ExpressionTokenType.Assign)
{
// todo -- would fail on this: var x = new F(() => { return x; });
tokenStream.Advance();
ASTNode expression = null;
if (!ParseTerminatedExpression(ref expression))
{
goto fail;
}
node = new LocalVariableNode()
{
name = name,
value = expression,
typeLookup = typeLookup // will be default for var
};
return(true);
}
fail:
{
parser.Release(false);
typeLookup.Release();
tokenStream.Restore();
return(false);
}
}