Your dec has a problem. Anything matched by /^[0-7]+$/ or /^\d+$/ is going to be
matched by /^(0x)?[0-9A-Fa-f]+$/i as well, so if you
do the tests in order you present it, it'll assume either hexadecimal, or binary. Reversing the order will give a problem as well. How would you distinguish between 1016 == 1610, 1010, and 108 == 810 (subscripts indicate base)?
in reply to A philosophical pondering concerning hexes
Of course, as pointed out, your fallacy lies in assuming that oct and hex return decimal representations of numbers - they don't. They return numbers:
It's a number - without a stringified valued.
$ perl -MDevel::Peek -wle 'Dump hex 10'
SV = IV(0x8192014) at 0x8181270
REFCNT = 1
FLAGS = (IOK,READONLY,pIOK)
IV = 16
Also, Perl already has a function to turn a number into a hexadecimal, octal or binary representation: it's called sprintf.