private LNode ParseExpr(IListSource <Token> tree)
{
if (_parser == null)
{
_parser = new EcsParser(tree, SourceFile, ErrorSink);
}
else
{
_parser.Reset(tree, SourceFile);
}
LNode expr = _parser.ExprStart(false);
return(expr);
}
public IListSource <LNode> Parse(IListSource <Token> input, ISourceFile file, IMessageSink msgs, Symbol inputType = null)
{
// For efficiency we'd prefer to re-use our _parser object, but
// when parsing lazily, we can't re-use it because another parsing
// operation could start before this one is finished. To force
// greedy parsing, we can call ParseStmtsGreedy(), but the caller may
// prefer lazy parsing, especially if the input is large. As a
// compromise I'll check if the source file is larger than a
// certain arbitrary size. Also, ParseExprs() is always greedy
// so we can always re-use _parser in that case.
bool exprMode = inputType == ParsingService.Exprs;
char _ = '\0';
if (inputType == ParsingService.Exprs || file.Text.TryGet(255, ref _))
{
EcsParser parser = _parser;
if (parser == null)
{
_parser = parser = new EcsParser(input, file, msgs);
}
else
{
parser.ErrorSink = msgs;
parser.Reset(input, file);
}
if (inputType == ParsingService.Exprs)
{
return(parser.ParseExprs());
}
else
{
return(parser.ParseStmtsGreedy());
}
}
else
{
var parser = new EcsParser(input, file, msgs);
return(parser.ParseStmtsLazy().Buffered());
}
}
public IListSource<LNode> Parse(IListSource<Token> input, ISourceFile file, IMessageSink msgs, Symbol inputType = null)
{
// For efficiency we'd prefer to re-use our _parser object, but
// when parsing lazily, we can't re-use it because another parsing
// operation could start before this one is finished. To force
// greedy parsing, we can call ParseStmtsGreedy(), but the caller may
// prefer lazy parsing, especially if the input is large. As a
// compromise I'll check if the source file is larger than a
// certain arbitrary size. Also, ParseExprs() is always greedy
// so we can always re-use _parser in that case.
bool exprMode = inputType == ParsingService.Exprs;
char _ = '\0';
if (inputType == ParsingService.Exprs || file.Text.TryGet(255, ref _)) {
EcsParser parser = _parser;
if (parser == null)
_parser = parser = new EcsParser(input, file, msgs);
else {
parser.ErrorSink = msgs ?? MessageSink.Current;
parser.Reset(input, file);
}
if (inputType == ParsingService.Exprs)
return parser.ParseExprs();
else
return parser.ParseStmtsGreedy();
} else {
var parser = new EcsParser(input, file, msgs);
return parser.ParseStmtsLazy().Buffered();
}
}
protected override void Stmt(string text, LNode expected, Action<EcsNodePrinter> configure = null, bool exprMode = false, Mode mode = Mode.Both)
{
if (mode == Mode.PrintOnly)
return;
// This is the easy way:
//LNode result = EcsLanguageService.Value.ParseSingle(text, MessageSink.Console, exprMode ? ParsingService.Exprs : ParsingService.Stmts);
// But to make debugging easier, I'll do it the long way:
ILexer<Token> lexer = EcsLanguageService.Value.Tokenize(new UString(text), "", MessageSink.Console);
var preprocessed = new EcsPreprocessor(lexer);
var treeified = new TokensToTree(preprocessed, false);
var parser = new EcsParser(treeified.Buffered(), lexer.SourceFile, MessageSink.Console);
LNode result = exprMode ? parser.ExprStart(false) : parser.Stmt();
AreEqual(TokenType.EOF, parser.LT0.Type());
AreEqual(expected, result);
}
