/// <summary>
/// Specfify the most part of the grammar for the parser
/// The remaining part of the grammar is defined the static <see cref="ExpressionParser"/>
/// constructor and limited by the <see cref="ExpressionParser.OnNewExpression"/> routine
/// </summary>
private void RegisterParselets(PrattParser parser)
{
parser.AddPrefix(TokenType.REAL, new RealParselet());
parser.AddPrefix(TokenType.LPAREN, new GroupParselet());
parser.AddPrefix(TokenType.PLUS, new PrefixOperatorParselet(PrecedenceTable.PREFIX));
parser.AddPrefix(TokenType.MINUS, new PrefixOperatorParselet(PrecedenceTable.PREFIX));
parser.AddPrefix(TokenType.ABS, new AbsFunctionParselet());
parser.AddInfix(TokenType.PLUS, new BinaryOperatorParselet(false, PrecedenceTable.SUM));
parser.AddInfix(TokenType.MINUS, new BinaryOperatorParselet(false, PrecedenceTable.SUM));
parser.AddInfix(TokenType.MUL, new BinaryOperatorParselet(false, PrecedenceTable.PROD));
parser.AddInfix(TokenType.DIV, new BinaryOperatorParselet(false, PrecedenceTable.PROD));
}
/// <summary>
/// Initializes a new instance of the parser with the expression
/// that should be parsed.
/// </summary>
/// <param name="text"></param>
/// <remarks>
/// Notice that the parser is a one-time-use object!
/// </remarks>
public ExpressionParser(string text)
{
_parser = new PrattParser(new Lexer(text), _ => RegisterParselets(_));
}