public override bool TryParse(TokenStack tokens, out GraphNode node)
{
if (tokens.ExpectSequence(TokenType.Identifier, TokenType.ColonSymbol))
{
var queue = new Queue <Token>();
var identifier = tokens.Pop();
var colon = tokens.Pop();
queue.Enqueue(identifier);
queue.Enqueue(colon);
var valueSyntax = new ValueSyntax();
var valueToken = tokens.Peek();
if (valueSyntax.TryParse(tokens, out GraphNode value))
{
queue.Enqueue(valueToken);
node = new VariableAssignment(queue, identifier.Value, (Value)value);
return(true);
}
else
{
while (queue.Count > 0)
{
tokens.Push(queue.Dequeue());
}
}
}
node = null;
return(false);
}
public override bool TryParse(TokenStack tokens, out GraphNode node)
{
var source = new Queue <Token>();
if (tokens.Expect(TokenType.Identifier))
{
var identifier = tokens.Pop();
source.Enqueue(identifier);
if (tokens.Expect(TokenType.ColonSymbol))
{
var colon = tokens.Pop();
source.Enqueue(colon);
var valueSyntax = new ValueSyntax();
if (valueSyntax.TryParse(tokens, out GraphNode value))
{
node = new EnumValue(source, identifier.Value, (Value)value);
return(true);
}
else
{
// TODO: syntax error
node = null;
return(false);
}
}
else
{
node = new EnumValue(source, identifier.Value, null);
return(true);
}
}
// TODO: syntax error
node = null;
return(false);
}