@bar can't hold the result of ||= since @bar is an array and the result is a scalar. The LHS of ||= must be a scalar lvalue.

The following will do what you want: 

@bar = (1,2,3) if !@bar;

[download]

I admit, the error message could be much clearer.

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

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