The following sets the var to 1 too, and it even looks similar, so it must be the same operator as the other two, right? 

my $var3 = 1;

[download]

Why does that bizarre logic keep surfacing? Operators are documented in perlop.

In fact, you should be using my $var = 1; in this case. I'm surprised no one has mentioned that it makes no sense for my $var to be the LHS of |= or ||=. 

my $var |= 1;
my $var2 ||= 1;

[download]
means 
my $var;
$var = $var | 1;
       ^^^^
       Known to be undef since it was just created.

my $var2;
$var2 = $var2 || 1;
        ^^^^^
        Known to be undef since it was just created.

[download]

In reply to Re: What is the difference between |= and ||=? by ikegami
in thread What is the difference between |= and ||=? by Anonymous Monk

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