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

My guess is that he means something like:

    $ perl -wle 'print oct 108'
    Illegal octal digit '8' ignored at -e line 1.
    8
[download]

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

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
[download]