wow incrementing with ++ is not orthogonal to +1!

  DB<33> my $y;$y++
  
  DB<34> my $y;$y+1
Use of uninitialized value $y in addition (+) at (eval 38)[/usr/share/
+perl/5.10/perl5db.pl:638] line 2.

[download]

from perlop

        The auto-increment operator has a little extra builtin magic t
+o it.
 
...(<i>special magic for incrementing strings, ie <c>++($x='x9') eq 'y
+0'</i>)...
 
       "undef" is always treated as numeric, and in particular is chan
+ged to 0
       before incrementing (so that a post-increment of an undef value
+ will
       return 0 rather than "undef").

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Cheers Rolf

In reply to Re^3: Numification of strings by LanX
in thread Numification of strings by LanX

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