/// <summary>
/// If the next token is a keyword with the given value, return that token after
/// advancing the parser. Otherwise, do not change the parser state and return
/// false.
/// </summary>
/// <param name="kind">The kind.</param>
/// <returns></returns>
/// <exception cref="SyntaxError"></exception>
protected Token Expect(TokenKind kind)
{
var token = Token;
if (token.Kind == kind)
{
Advance();
return(token);
}
throw new SyntaxError(Source, token.Start,
$"Expected {TokenKindHelpers.GetTokenKindDesc(kind)}, found {token.GetTokenDesc()}");
}
/// <summary>
/// A helper function to describe a token as a string for debugging
/// </summary>
/// <returns></returns>
public string GetTokenDesc()
{
return(String.IsNullOrEmpty(Value)
? TokenKindHelpers.GetTokenKindDesc(Kind)
: $"{TokenKindHelpers.GetTokenKindDesc(Kind)} \"{Value}\"");
}