/*
* number = [ minus ] int [ frac ] [ exp ]
* decimal-point = %x2E ; .
* digit1-9 = %x31-39 ; 1-9
* e = %x65 / %x45 ; e E
* exp = e [ minus / plus ] 1*DIGIT
* frac = decimal-point 1*DIGIT
* int = zero / ( digit1-9 *DIGIT )
* minus = %x2D ; -
* plus = %x2B ; +
* zero = %x30 ; 0
*/
private object ParseNumber(ITypeBuilderRegistry registry, ITypeBuilder builder)
{
var startLine = Line;
var startColumn = Column;
var sb = new StringBuilder();
if (Peek() == '-')
{
sb.Append(Next());
}
var hasInteger = false;
while (char.IsDigit((char) Peek()))
{
sb.Append(Next());
hasInteger = true;
}
if (!hasInteger)
{
throw CreateExpectedNumberException(startLine, startColumn);
}
if (Peek() != '.')
{
long intValue;
if (!long.TryParse(sb.ToString(), out intValue))
{
throw CreateExpectedNumberException(startLine, startColumn);
}
return builder.CreateNumber(registry, intValue);
}
sb.Append(Next());
var hasFrac = false;
while (char.IsDigit((char) Peek()))
{
sb.Append(Next());
hasFrac = true;
}
if (!hasFrac)
{
throw CreateExpectedNumberException(startLine, startColumn);
}
if ("eE".IndexOf((char) Peek()) >= 0)
{
sb.Append(Next());
if ("+-".IndexOf((char) Peek()) >= 0)
{
sb.Append(Next());
}
var hasExp = false;
while (char.IsDigit((char) Peek()))
{
sb.Append(Next());
hasExp = true;
}
if (!hasExp)
{
throw CreateExpectedNumberException(startLine, startColumn);
}
}
double doubleValue;
if (!double.TryParse(sb.ToString(),
NumberStyles.AllowLeadingSign | NumberStyles.AllowDecimalPoint |
NumberStyles.AllowExponent,
JsonFormats.DoubleFormat, out doubleValue))
{
throw CreateExpectedNumberException(startLine, startColumn);
}
return builder.CreateNumber(registry, doubleValue);
}