Hi monks,
in an attempt to run a script as stand-alone that usually is called from within another script with a "do 'script'" statement I attempted to conditionally define some variables.
The two 3-liners below - the first one simulating a call from a script with $var defined - the second one the stand-alone context - emulate the situation.
Script1:
my $var = "xxx\n";
my $var="zzz\n" unless defined($var);
print $var;

[download]

Script2:
#my $var = "xxx\n";
my $var="zzz\n" unless defined($var);
print $var;

[download]

As a result the first script prints nothing.
When called with perl -w I get the output:
"my" variable $var masks earlier declaration in same scope at unlesste
+st.pl line 2.
Use of uninitialized value in print at unlesstest.pl line 3.

[download]

Both error messages make no sense to me and seem to be contradicting each other.
The output of the second script is:
Name "main::var" used only once: possible typo at unlesstest.pl line 2
+.
zzz

[download]
Even so this time the line is printed the warning about an undefined variable inside a defined() context does not make a lot of sense to me.
Anyone with an explanation and possibly a solution for my problem?

Thanks

In reply to conditional definition of variables by stephanm

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