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in reply to A philosophical pondering concerning hexes

I like the idea you are presenting but I balk at your interpretation that oct() and hex() convert or return decimal. They consume a properly formed string and return a number. Perl happens to stringify numbers as their decimal representation. It is only incidental that print hex "0x20" appears to be a hex_string->decimal converter. It is just a hex_string->number converter.

I am not quite sure what the name for numify_hex_string() should be. unhex() is awkward and is still not descriptive of its function.

I also note that oct() doesn't happily consume non-octal data. It just screws up when you do that.

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Re^2: A philosophical pondering concerning hexes
by tinita (Parson) on Jun 24, 2004 at 11:08 UTC
    I also note that oct() doesn't happily consume non-octal data. It just screws up when you do that.
    huh? oct("0xf") will happily return 15. "0xf" is non-octal in my view...
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      My guess is that he means something like: 
          $ perl -wle 'print oct 108'
    Illegal octal digit '8' ignored at -e line 1.
    8

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      To me, this is just what's Perl is about; regardless of what you throw at it, it does it utter best to make something out of it, and it issues a warning there's something odd about the input. Although in this case, it isn't just Perl that does so - the C functions strtol, and atoi and friends also consume initial portions of a string, stopping at the first character that isn't valid.

      Abigail

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        No, I didn't give oct a valid hex number, I gave it an invalid octal number which could have been understood as an otherwise valid decimal number. I had not previously considered that oct() would consume a hex number but since it is implemented using a function shared with hex, I suppose that makes sense.

        perl -wle 'print oct "108"'
Illegal octal digit '8' ignored at -e line 1.
8

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