Number::Compare compiles a simple comparison to an anonymous subroutine, which you can call with a value to be tested again.
Now this would be very pointless, if Number::Compare didn't understand magnitudes.
The target value may use magnitudes of kilobytes (k, ki), megabytes (m, mi), or gigabytes (g, gi). Those suffixed with an i use the appropriate 2**n version in accordance with the IEC standard: http://physics.nist.gov/cuu/Units/binary.html