http://www.perlmonks.org?node_id=232945


in reply to my least favorite perl feature

How does Python handle the dofference/similarity here?

print '100 is numerically ', 100 == $_ ? ' the same ' :' different, ', + 'and lexically ', 100 eq $_ ? ' the same ' : ' different', ' to ', + "$_", $/ for qw[100 100.0 1e2 .1e3 1000e-1] 100 is numerically the same and lexically the same to 100 100 is numerically the same and lexically different to 100.0 100 is numerically the same and lexically different to 1e2 100 is numerically the same and lexically different to .1e3 100 is numerically the same and lexically different to 1000e-1

Examine what is said, not who speaks.

The 7th Rule of perl club is -- pearl clubs are easily damaged. Use a diamond club instead.

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Re^2: my least favorite perl feature
by adrianh (Chancellor) on Feb 05, 2003 at 17:47 UTC

    I don't have a python interpreter to double check - but I'm pretty sure that python == would be true for all the pairs of numbers you give (since numbers are automatically converted to a common type in python comparisons.)

    <update>If they are numbers I mean. For strings only "100" == "100" returns true, all others false. If one a string and the other a number, always false.</update>

    For objects == is true in python if they are the same object (in perl refaddr($o1) == refaddr($o2).

    For full details see this bit of the python docs.

my real point
by waxmop (Beadle) on Feb 05, 2003 at 17:05 UTC
    is that python's == operator can be used to test different objects, like tuples, class objects, whatever.

      a) I'd still like to see the answer to the preceeding question as I have no knowledge of how Python would differeciate the examples I gave.

      b) Could you give a couple of examples of where you use == in Python where you cannot in Perl? Again partly for my interest, partly because it ia easier understand you meaning from concrete examples than nebulous statements.


      Examine what is said, not who speaks.

      The 7th Rule of perl club is -- pearl clubs are easily damaged. Use a diamond club instead.