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Re: NaN+NaNi

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Aaron Sherman
October 11, 2001 10:27
Re: NaN+NaNi
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On Thu, Oct 11, 2001 at 10:28:34AM -0500, Jonathan Scott Duff wrote:
> On Thu, Oct 11, 2001 at 11:13:59AM -0400, Dan Sugalski wrote:
> > As for more complex string literals evaluating to numbers, I think that's 
> > something best left to either a user-written sub, or user-written fancy 
> > parser hacks. Up to Larry whether it goes in the base language, but I think 
> > I'd prefer not.
> Speaking of string turning into numbers ...
> It's bothered me that I can write 100_000 in my perl code, but if I have
> a string "100_000" it'll evaluate to 100 when numerified. It would be
> really weird if "10indigo" became 10i, "1e3foobar" became 1000, and
> "10_000" became 10 in Perl 6 IMHO.

Perl's been very consistent in not handling strange things in its
string-to-number conversion because of the god-awful string processing
code that a lot of people have to write to handle stupid file formats.

For example, zero-filled numbers are not converted to octal because
many text files contain zero-filled numbers.

The idea that "0cat" is "0", but "0xat" is 10 will confuse a lot of folk.

If strings in numeric context are treated the same way as the parser
would, then I think there need to be warnings for trailing garbage.

No, I think if you want "10_000" to be 10000, you can always
eval it, but I don't think anyone reading in text should expect

Aaron Sherman		finger for GPG info. Fingerprint:	6DC1 F67A B9FB 2FBA D04C  619E FC35 5713 2676 CEAF
  "Write your letters in the sand for the day I'll take your hand
   In the land that our grandchildren knew." -Queen/_'39_

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