private Exp ParseExp()
{
var term = ParseFactor();
while (PeekAndDiscard(TokenType.Minus))
{
var term2 = ParseFactor();
term = new BinExp(TokenType.Minus, term, term2);
}
return(term);
}
public Exp ParseExp()
{
var term = ParseTerm();
for (; ;)
{
var type = lexer.Peek().Type;
switch (type)
{
case TokenType.Plus: break;
case TokenType.Minus: break;
default: return(term);
}
lexer.Read();
var term2 = ParseTerm();
term = new BinExp(type, term, term2);
}
}
private Exp ParseTerm()
{
var factor = ParseFactor();
for (; ;)
{
var opType = lexer.Peek().Type;
switch (opType)
{
case TokenType.Star:
case TokenType.Slash:
break;
default:
return(factor);
}
lexer.Read();
var factor2 = ParseFactor();
factor = new BinExp(opType, factor, factor2);
}
}
