private static FlowNode ParseIf(RuleContext rule)
{
//IF expression INDENT statements DEDENT (ELSE INDENT statements DEDENT)?;
ExpressionNode expression = ExpressionParser.ParseExpression((RuleContext)rule.GetChild(1));
BlockNode trueBlock = ParseBlockNode((RuleContext)rule.GetChild(3));
//Pure if
if (rule.ChildCount == 5)
{
return(CrawlSyntaxNode.If(rule.SourceInterval, expression, trueBlock));
}
//If Else
else if (rule.ChildCount == 9)
{
BlockNode falseBlock = ParseBlockNode((RuleContext)rule.GetChild(7));
return(CrawlSyntaxNode.IfElse(rule.SourceInterval, expression, trueBlock, falseBlock));
}
//Else if
else if (rule.ChildCount == 7)
{
RuleContext chain = (RuleContext)rule.GetChild(6);
List <CrawlSyntaxNode> blockContents = new List <CrawlSyntaxNode>()
{
ParseIf(chain)
};
BlockNode falseBlock = CrawlSyntaxNode.Block(chain.SourceInterval, blockContents);
return(CrawlSyntaxNode.IfElse(rule.SourceInterval, expression, trueBlock, falseBlock));
}
throw new NotImplementedException("if statement with strange argument counts (this is probably else if)");
}
//public static ConstructNode ParseConstruct(RuleContext rule)
public static BlockNode ParseBlockNode(RuleContext rule)
{
System.Collections.IEnumerable meaningfullContent;
if (rule.RuleIndex == CrawlParser.RULE_statements)
{
meaningfullContent = rule.AsIEnumerable();
}
else if (rule.RuleIndex == CrawlParser.RULE_class_body)
{
meaningfullContent = rule.AsEdgeTrimmedIEnumerable();
}
else
{
throw new NotImplementedException("Probably broken");
}
IEnumerable <CrawlSyntaxNode> contents =
meaningfullContent
.OfType <RuleContext>() //FIXME! This can contain raw NEWLINE and END_OF_STATEMENT tokens which is TerminalNodeImpl not RuleContext. Not happy about discarding that trivia
.Select(ParseStatement).ToList();
return(CrawlSyntaxNode.Block(rule.SourceInterval, contents));
}