} // ParseIdentifier
// Parse a numeric literal beginning at the current stream location.
private Token ParseNumber(SrcLoc loc)
{
// Get a buffer from which we can parse the number.
char[] charBuf;
int startPos;
int bufLen = buffer.GetBuffer( maxTokenLen, out charBuf,
out startPos );
if (bufLen > maxTokenLen)
bufLen = maxTokenLen;
// Find the end of the number. We match for the following
// components:
//
// integer part (1 or more digits)
// optional fractional part ('.' plus one or more digits)
// optional exponent ('E' or 'e', optional '+' or '-', and 1-3 digits)
//
// HACK SN 7/14/01: for now, we aren't enforcing that the fractional
// part must have at least one digit, or that the exponent must have
// at least 1 and no more than 3 digits. Review the ECMAScript spec for
// the correct rules. Also, should we allow numbers that begin with a '.'
// (no integer part)?
int tokenLen = 0;
while ( tokenLen < bufLen &&
CharUtils.IsDigitChar(charBuf[startPos+tokenLen]) )
tokenLen++;
if (tokenLen < bufLen && charBuf[startPos+tokenLen] == '.')
{
tokenLen++;
while ( tokenLen < bufLen &&
CharUtils.IsDigitChar(charBuf[startPos+tokenLen]) )
tokenLen++;
}
if ( tokenLen < bufLen &&
( charBuf[startPos+tokenLen] == 'E' ||
charBuf[startPos+tokenLen] == 'e' ) )
{
tokenLen++;
if ( tokenLen < bufLen &&
( charBuf[startPos+tokenLen] == '+' ||
charBuf[startPos+tokenLen] == '-' ) )
tokenLen++;
while ( tokenLen < bufLen &&
CharUtils.IsDigitChar(charBuf[startPos+tokenLen]) )
tokenLen++;
}
NumLit token = new NumLit();
token.rawText = buffer.ConsumeString(tokenLen);
loc.len = tokenLen;
token.loc = loc;
try
{
token.value = Double.Parse(token.rawText);
}
catch (FormatException e)
{
throw new ParseError( "FormatException parsing numeric literal \"" +
token.rawText + "\": " + e.ToString(),
loc );
}
catch (OverflowException e)
{
throw new ParseError( "OverflowException parsing numeric literal \"" +
token.rawText + "\": " + e.ToString(),
loc );
}
return token;
} // ParseNumber
} // ParseIdentifier
// Parse a numeric literal beginning at the current stream location.
private Token ParseNumber(SrcLoc loc)
{
// Get a buffer from which we can parse the number.
char[] charBuf;
int startPos;
int bufLen = buffer.GetBuffer(maxTokenLen, out charBuf,
out startPos);
if (bufLen > maxTokenLen)
{
bufLen = maxTokenLen;
}
// Find the end of the number. We match for the following
// components:
//
// integer part (1 or more digits)
// optional fractional part ('.' plus one or more digits)
// optional exponent ('E' or 'e', optional '+' or '-', and 1-3 digits)
//
// HACK SN 7/14/01: for now, we aren't enforcing that the fractional
// part must have at least one digit, or that the exponent must have
// at least 1 and no more than 3 digits. Review the ECMAScript spec for
// the correct rules. Also, should we allow numbers that begin with a '.'
// (no integer part)?
int tokenLen = 0;
while (tokenLen < bufLen &&
CharUtils.IsDigitChar(charBuf[startPos + tokenLen]))
{
tokenLen++;
}
if (tokenLen < bufLen && charBuf[startPos + tokenLen] == '.')
{
tokenLen++;
while (tokenLen < bufLen &&
CharUtils.IsDigitChar(charBuf[startPos + tokenLen]))
{
tokenLen++;
}
}
if (tokenLen < bufLen &&
(charBuf[startPos + tokenLen] == 'E' ||
charBuf[startPos + tokenLen] == 'e'))
{
tokenLen++;
if (tokenLen < bufLen &&
(charBuf[startPos + tokenLen] == '+' ||
charBuf[startPos + tokenLen] == '-'))
{
tokenLen++;
}
while (tokenLen < bufLen &&
CharUtils.IsDigitChar(charBuf[startPos + tokenLen]))
{
tokenLen++;
}
}
NumLit token = new NumLit();
token.rawText = buffer.ConsumeString(tokenLen);
loc.len = tokenLen;
token.loc = loc;
try
{
token.value = Double.Parse(token.rawText);
}
catch (FormatException e)
{
throw new ParseError("FormatException parsing numeric literal \"" +
token.rawText + "\": " + e.ToString(),
loc);
}
catch (OverflowException e)
{
throw new ParseError("OverflowException parsing numeric literal \"" +
token.rawText + "\": " + e.ToString(),
loc);
}
return(token);
} // ParseNumber
