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Excellent tutorial for me(newbie)
and yes Hugo, your example made it clear for me as I wrote out your example
use strict; sub foo { print "\$a is ", defined($a) ? $a : 'undef', $/; print "\$b is ", defined($b) ? $b : 'undef', $/; } print "Just before start of scope\n"; { print "Just after start of scope\n"; my $a = 1; local $b = 1; print "a=$a, b=$b\n"; foo(); print "Just before end of scope\n"; } print "Just after end of scope\n"; print "\$a is ", defined($a) ? $a : 'undef', $/; print "\$b is ", defined($b) ? $b : 'undef', $/;
Couple other questions/comments
1)using input record separator as newline indicator is very interesting. Never seen it before but works well. Any reason?
I am assuming it's just a style issue?
2)Below code from tutorial does not work when I insert my next to variable.. can someone explain this?
[root@myserver tmp]# cat -n !$ cat -n ./per_begin.pl1 1 #!/usr/bin/perl -w 2 3 use strict; 4 5 6 my $x = "original state"; 7 8 sub foo { 9 print " \$x is: $x\n"; 10 } 11 12 { # beginning of lexical scope 13 14 local $x = "altered state"; 15 foo(); 16 17 } # end of lexical scope 18 print "\$x is: $x\n"; [root@myserver tmp]# ./!$ ././per_begin.pl1 Can't localize lexical variable $x at ././per_begin.pl1 line 14.
3)can someone explain further on "lexical variables are declared at compile-time, not initialised?
Is this because BEGIN runs during compile-time? I sneaked in a new my $foo = something inside of BEGIN
block and execution of the code came out w/ foo is something during BEGIN phase

In reply to Re^3: Lexical scoping like a fox by convenientstore
in thread Lexical scoping like a fox by broquaint

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