On Mon, Feb 6, 2012 at 3:11 PM, Mark Miesfeld <[email protected]> wrote: > On Mon, Feb 6, 2012 at 11:59 AM, Rick McGuire <[email protected]> wrote: >> >> >> Whether it is a number or not is not the issue. The issue is whether >> it is considered a symbol or not during scanning. For example, 3a is >> a symbol token, and it is only when you try to do arithmetic with its >> value do any numeric rules get applied. At issue here is whether the >> scanner rules for exponential notation require this to be interpreted >> as a single token, or two tokens with an operator between. By the >> rules we have in our documentation, then 3ae+6, 3..0+6, and .ae+6 >> should all be single tokens. Prior to that "bug fix", only the first >> of these was interpreted as a single symbol token. After the update, >> none of these were. Our working definition, I believe, goes all the >> way back to Mike's original definition. However, I think I just found >> the relevant section in the ANSI standard, which states: >> >> – EXPONENT_SIGN occurs when the character about to be scanned is '+' >> or '-', and the >> characters to the left of the sign, currently parsed as part of >> Const_symbol, represent a >> plain_number followed by 'E' or 'e', and the characters to the right >> of the sign represent a >> repetition of digit not followed by a general_letter or '.'. >> >> So, by this definition, the exponent is only recognized as part of the >> symbol if the token scanned so far is a "plain number" (consisting of >> at least one digit and at most one "."). So by the ANSI definition, >> 3ae+6 should NOT be treated as a single token, but rather as two >> tokens with a operator between then. The error is the correct >> behavior here, and this truly was a bug fix :-) >> > > Okay, thanks for straightening that out. I didn't have the ANSI standard, > but I just downloaded the pre-publication from RexxLA. Not sure if would > have found that part eventually or not. <grin> > > Does our working definition in the docs need to be updated?
It probably should be. I'll take a crack at updating the wording. Rick > > -- > Mark Miesfeld > > ------------------------------------------------------------------------------ > Try before you buy = See our experts in action! > The most comprehensive online learning library for Microsoft developers > is just $99.99! Visual Studio, SharePoint, SQL - plus HTML5, CSS3, MVC3, > Metro Style Apps, more. Free future releases when you subscribe now! > http://p.sf.net/sfu/learndevnow-dev2 > _______________________________________________ > Oorexx-devel mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/oorexx-devel > ------------------------------------------------------------------------------ Try before you buy = See our experts in action! The most comprehensive online learning library for Microsoft developers is just $99.99! Visual Studio, SharePoint, SQL - plus HTML5, CSS3, MVC3, Metro Style Apps, more. Free future releases when you subscribe now! http://p.sf.net/sfu/learndevnow-dev2 _______________________________________________ Oorexx-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/oorexx-devel
