private static void Initialize()
{
if (_initialized)
{
return;
}
_initialized = true;
_lexer = new Lexer();
_lexer.AddIgnore(@"\s+");
var suffix = _lexer.Add("²|³|°", "SUFFIX");
var prefix = _lexer.Add(@"√|∛|abs|acos|arg|asin|atan|cbrt|cnj|cosh?|deg|exp|im|ln|rad|rcp|re|sinh?|sqrt|tanh?", "PREFIX");
var prefix2 = _lexer.Add(@"log_|root_", "PREFIX2");
var infix0 = _lexer.Add(@"\^", "INFIX0");
var infix1 = _lexer.Add(@"[*/×÷∠]", "INFIX1");
var infix2 = _lexer.Add(@"[-－+＋]", "INFIX2");
var number = _lexer.Add(@"[0-9]+([.][0-9]*)?i?|[.][0-9]+i?|i", "NUMBER");
var open = _lexer.Add(@"\(", "(");
var close = _lexer.Add(@"\)", ")");
var variable = _lexer.Add(@"x", "x");
var constant = _lexer.Add(@"[eπ|pi]", "CONST");
var expr = Patterns.Choice <Expression>("expr");
var factor1 = Patterns.Choice(
number.Map(t => Expression.Constant(ParseComplex(t.Text))),
constant.Map(t => Expression.Constant(GetConst(t.Text))),
variable.Map(t => (Expression)X),
Patterns.Seq(open, expr, close, (_, x, __) => x),
Patterns.Seq(open, expr, (_, x) => x, ""));
var factor2 = Patterns.Choice <Expression>("factor");
factor2.AddRange(
factor1,
Patterns.Seq(factor2, suffix, (x, t) => Invoke(GetUnary(t.Text), x), "", Priority.Left(20)),
Patterns.Seq(factor2, infix0, factor2, (x, t, y) => Invoke(GetBinary(t.Text), x, y), "", Priority.Right(19)));
var term2 = Patterns.Choice <Expression>("term2");
var term1 = Patterns.Choice <Expression>("term1");
term1.AddRange(factor2,
Patterns.Seq(factor2, term1, (left, right) => Expression.Multiply(left, right), "", Priority.Right(15)),
Patterns.Seq(prefix, term2, (t, x) => Invoke(GetUnary(t.Text), x), "", Priority.Right(15)),
Patterns.Seq(prefix, suffix, term2, (t, u, x) => Invoke(GetUnary(u.Text), Invoke(GetUnary(t.Text), x)), "", Priority.Right(15)),
Patterns.Seq(prefix, infix0, factor2, term2, (t, u, y, x) => Invoke(GetBinary(u.Text), Invoke(GetUnary(t.Text), x), y), "", Priority.Right(15)),
Patterns.Seq(prefix2, factor2, term2, (t, y, x) => Invoke(GetBinary(t.Text), x, y), "", Priority.Right(15)));
term2.AddRange(term1,
Patterns.Seq(infix2, term2, (t, x) => Invoke(GetUnary(t.Text), x), "", Priority.Right(15)));
expr.AddRange(
term2,
Patterns.Seq(expr, infix1, expr, (x, t, y) => Invoke(GetBinary(t.Text), x, y), "", Priority.Left(9)),
Patterns.Seq(expr, infix2, expr, (x, t, y) => Invoke(GetBinary(t.Text), x, y), "", Priority.Left(8)));
_parser = expr.CreateParser();
}