I've actually run into this problem before. Correct me if I'm wrong, but the code that isn't working for you is:

push $cond > 0 ? @a : @b , $elem;

I remember reading somewhere that the ternary binds more closely than the conditional. This means that the ternary operator sees only the 0, assumes it to be a false condition, and then reports @a back to the conditional statement. @a would then be evaluated in scalar context and compared to $code. No matter what the result, this eventually means that push will be getting a boolean value (which may be null) instead of an array to push into. To fix this, simply enclose the conditional statement in parentheses, as below. This forces the conditional to evaluate first, followed by the ternary, which then reports to push.

push ($cond > 0) ? @a : @b , $elem;

This is what has worked for me in the past. I'm currently on a handicapped (perl-less) machine, so I'm not able to test it. Someone please test and confirm.

Update: This explanation is completely wrong, and does not even work, as explained below. The problem is instead related to the prototyping in push. My deepest apologies. Next time I will wait to consult the texts before answering.

In reply to Re: Using ternary operator as lvalue in push by dogz007
in thread Using ternary operator as lvalue in push by oha

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