public override ParseTreeResult <IList <IParseTree <TToken, TRule> > > TryParse(
IList <Token <TToken> > tokens,
int matchFrom,
IDictionary <TRule, RuleDefinition> rulesByType)
{
if (matchFrom >= tokens.Count)
{
return(this.AllowZero
? RuleElementResult.Empty(matchFrom, matchFrom)
: RuleElementResult.Error(matchFrom, matchFrom));
}
var currentParseTree = rulesByType[this.RuleType]
.TryParse(tokens, matchFrom, rulesByType);
if (currentParseTree.IsError)
{
return(this.AllowZero
? RuleElementResult.Empty(matchFrom, currentParseTree.MaxMatchedNextTokenIndex)
: RuleElementResult.Error(currentParseTree.NextTokenIndex, currentParseTree.MaxMatchedNextTokenIndex));
}
var matches = new List <IParseTree <TToken, TRule> >();
if (currentParseTree.HasTreeItems)
{
matches.Add(currentParseTree.TreeItems);
}
matchFrom = currentParseTree.NextTokenIndex;
var maxMatchedNextTokenIndex = currentParseTree.MaxMatchedNextTokenIndex;
if (this.AllowMany)
{
while (matchFrom < tokens.Count)
{
currentParseTree = rulesByType[this.RuleType]
.TryParse(tokens, matchFrom, rulesByType);
if (currentParseTree.IsError)
{
break;
}
if (currentParseTree.HasTreeItems)
{
matches.Add(currentParseTree.TreeItems);
}
matchFrom = currentParseTree.NextTokenIndex;
maxMatchedNextTokenIndex = currentParseTree.MaxMatchedNextTokenIndex;
}
}
return(RuleElementResult.NonEmpty(
this.hoist ? matches.Elements().ToList() : matches,
matchFrom,
maxMatchedNextTokenIndex));
}
public override ParseTreeResult <IList <IParseTree <TToken, TRule> > > TryParse(
IList <Token <TToken> > tokens,
int matchFrom,
IDictionary <TRule, RuleDefinition> rulesByType)
{
if (matchFrom >= tokens.Count)
{
return(this.AllowZero
? RuleElementResult.Empty(matchFrom, matchFrom)
: RuleElementResult.Error(matchFrom, matchFrom));
}
if (!tokens[matchFrom].Type.Equals(this.tokenType))
{
return(this.AllowZero
? RuleElementResult.Empty(matchFrom, matchFrom)
: RuleElementResult.Error(matchFrom, matchFrom));
}
var matches = this.exclude
? null
: new List <IParseTree <TToken, TRule> > {
new ParseTreeToken(tokens[matchFrom])
};
++matchFrom;
if (this.AllowMany)
{
while (matchFrom < tokens.Count && tokens[matchFrom].Type.Equals(this.tokenType))
{
matches?.Add(new ParseTreeToken(tokens[matchFrom]));
++matchFrom;
}
}
return(RuleElementResult.NonEmpty(matches, matchFrom, matchFrom));
}