public IExpression GetParseExp(int ctxPrecedence)
{
var prefixToken = _scanner.Consume();
if (prefixToken.IsEmpty)
{
return(null);
}
return(PrefixParse(prefixToken, ctxPrecedence));
}
public static List <TextSpan> ConsumeList(this IScanner scanner, params SqlToken[] tokenTypeList)
{
scanner.IgnoreComments();
var textSpanList = new List <TextSpan>();
foreach (var tokenType in tokenTypeList)
{
textSpanList.Add(scanner.Consume <SqlToken>(tokenType));
}
return(textSpanList);
}
public static bool MatchAny(this IScanner scanner, params SqlToken[] tokenTypeList)
{
scanner.IgnoreComments();
var expectTokenTypeList = tokenTypeList.Select(x => x.ToString()).ToList();
var span = scanner.Peek();
if (!expectTokenTypeList.Contains(span.Type))
{
return(false);
}
scanner.Consume();
return(true);
}
public static bool TryConsumeStringAny <TTokenType>(this IScanner scanner, out string token, params TTokenType[] expectTokenTypeList)
where TTokenType : struct
{
var span = scanner.Peek();
var expectTokenTypeStrList = expectTokenTypeList.Select(x => x.ToString());
if (!expectTokenTypeStrList.Contains(span.Type))
{
token = string.Empty;
return(false);
}
scanner.Consume();
token = scanner.GetSpanString(span);
return(true);
}
public static bool TryConsumeAny <TTokenType>(this IScanner scanner, out TextSpan outSpan, params TTokenType[] tokenTypes)
where TTokenType : struct
{
for (var i = 0; i < tokenTypes.Length; i++)
{
var tokenType = tokenTypes[i].ToString();
var token = scanner.Peek();
if (token.Type == tokenType)
{
scanner.Consume();
outSpan = token;
return(true);
}
}
outSpan = TextSpan.Empty;
return(false);
}
public static TextSpan ConsumeAny <TTokenType>(this IScanner scanner, params TTokenType[] tokenTypes)
where TTokenType : struct
{
for (var i = 0; i < tokenTypes.Length; i++)
{
var tokenType = tokenTypes[i].ToString();
var token = scanner.Peek();
if (token.Type == tokenType)
{
scanner.Consume();
return(token);
}
}
var helpMessage = scanner.GetHelpMessage(scanner.Peek());
var tokenTypesStr = string.Join(",", tokenTypes.Select(x => x.ToString()));
throw new ScanException($"Expect one of {tokenTypesStr}.\r\n{helpMessage}");
}
public TextSpan Consume(string expect = null)
{
return(_scanner.Consume(expect));
}
public static TextSpan Consume(this IScanner scanner, SqlToken tokenType)
{
scanner.IgnoreComments();
return(scanner.Consume <SqlToken>(tokenType));
}
