Well, it does work, as local not only squirrels away the old global value, but sets it to undef for the loop. However, upon writing some example code, I noticed a strange difference between two global variables, $/ and $^T. Both mean something, and always have values (and are thus defined) at the start of a script. However, $/ gets set to undef when used with a local, while $^T gets set to "0". [Luckily, $/ does not get set to 0, or my examples would not work. :)] Anyone know why $^T acts like that? Here's the code, and the results. This is perl 5.005_03, FWIW.

$MY  = 1;
$LOC = 1;
{
  local $LOC; local $LOC2; local $/; local $^T;
  my $MY; my $MY2;

  printf "LOC  defined: %s\n", defined $LOC  ? "YES" : "NO";
  printf "LOC2 defined: %s\n", defined $LOC2 ? "YES" : "NO";
  printf "IRS  defined: %s\n", defined $/    ? "YES" : "NO";
  printf "TIME defined: %s\n", defined $^T   ? "YES" : "NO";
  printf "MY   defined: %s\n", defined $MY   ? "YES" : "NO";
  printf "MY2  defined: %s\n", defined $MY2  ? "YES" : "NO";

  print "  LOC=$LOC, LOC2=$LOC2, TIME=$^T, IRS=$/, MY=$MY, MY2=$MY2\n"
+;
}
print "AFTER LOOP:\n";
print "  LOC=$LOC, LOC2=$LOC2, TIME=$^T, IRS=$/, MY=$MY, MY2=$MY2\n";

[download]

Which produces:

LOC  defined: NO
LOC2 defined: NO
IRS  defined: NO
TIME defined: YES
MY   defined: NO
MY2  defined: NO
  LOC=, LOC2=, TIME=0, IRS=, MY=, MY2=
AFTER LOOP:
  LOC=1, LOC2=, TIME=960648360, IRS=
, MY=1, MY2=

[download]

In reply to RE: RE: RE: Hard Lessons by turnstep
in thread Hard Lessons by Odud

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