$ perl -MO=Deparse -e '@bar ||= (1,2,3)'
Can't modify array dereference in logical or assignment (||=) at -e li
+ne 1, at EOF
-e had compilation errors.
@bar ||= ('???', '???', 3);

$ perl -MO=Deparse -we '@foo ||= 1'
Can't modify array dereference in logical or assignment (||=) at -e li
+ne 1, at EOF
-e had compilation errors.
BEGIN { $^W = 1; }
@foo ||= 1;

[download]
So it seems that ||= generally isn't supported in perl.

Update: ok, other monks explained why. ||= returns a scalar.

A quick code search shows that all examples "out there" use it only in lines that are commented out, so it seems to be a common mistake actually

In reply to Re: ||= oddity by moritz
in thread ||= oddity by throop

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