private object CreateHexIntegerLiteral(char first)
{
CharBuilder cb = new CharBuilder();
cb.Append(first);
cb.Append(ReadChar());//x or X (ever tested before)
double val = 0;
while (CanAdvance)
{
char next = PeekChar();
switch (next)
{
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
{
cb.Append(next);
val = val * 16 + next - '0';
ReadChar();
continue;
}
case 'a':
case 'b':
case 'c':
case 'd':
case 'e':
case 'f':
{
cb.Append(next);
val = val * 16 + next - 'a' + 10;
ReadChar();
continue;
}
case 'A':
case 'B':
case 'C':
case 'D':
case 'E':
case 'F':
{
cb.Append(next);
val = val * 16 + next - 'A' + 10;
ReadChar();
continue;
}
}
break;
}
return(int.Parse(cb.ToString()));
}
private object CreateOctalIntegerLiteral(char first)
{
var cb = new CharBuilder();
cb.Append(first);//0
double val = 0;
while (CanAdvance)
{
char next = PeekChar();
switch (next)
{
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
{
cb.Append(next);
val = val * 8 + next - '0';
ReadChar();
continue;
}
}
break;
}
return(int.Parse(cb.ToString()));
}
public string ReadString()
{
CharBuilder cb = new CharBuilder();
for (; c != '`'; c = ReadChar())
{
cb.Append(c);
}
return(cb.ToString());
}
public string ReadVariableName()
{
CharBuilder cb = new CharBuilder();
for (; char.IsLetterOrDigit(c) || c == '_'; c = ReadChar())
{
cb.Append(c);
}
c = FallBack();
return(cb.ToString());
}
public string ReadTypeName()
{
CharBuilder cb = new CharBuilder();
//todo use do while
for (; char.IsLetterOrDigit(c) || c == '_' || c == '.'; c = ReadChar())
{
cb.Append(c);
}
c = FallBack();
return(cb.ToString());
}
private object ReadNumber(char first)
{
CharBuilder builder = new CharBuilder();
builder.Append(first);
int dot = 0;
int exp = 0;
while (CanAdvance)
{
char next = PeekChar();
switch (next)
{
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
{
builder.Append(next);
ReadChar();
continue;
}
case '.':
//skip .
ReadChar();
next = PeekChar();
if (char.IsDigit(next))
{
dot++;
//add .
builder.Append('.');
builder.Append(next);
//skip digit
ReadChar();
if (dot > 1)
{
break;
}
continue;
}
FallBack();
break;
case 'e':
case 'E':
{
builder.Append(next);
c = ReadChar();
exp++;
if (exp > 1)
{
break;
}
next = PeekChar();
if (next == '+' || next == '-')
{
builder.Append(next);
ReadChar();
}
continue;
}
}
break;
}
if (dot > 0)
{
return(double.Parse(builder.ToString()));
}
else
{
return(int.Parse(builder.ToString()));
}
}