Yes, that matches what this node relies on, that local works by saving the old value and restoring it, exactly like assignments would. In your example, $obj is always pointing to the same SV.

However, using Alias, e.g. from the module:

@DYNAMIC = qw(m n o); { local @DYNAMIC; alias DYNAMIC => $tmp, PERM => $tmp; $DYNAMIC[2] = 'zzz'; # prints "abzzzd|abzzzd|abzzzd" print @$tmp, "|", @DYNAMIC, "|", @PERM, "\n"; } # prints "mno|pqr" print @DYNAMIC, "|", @PERM, "\n";
The Alias re-binds the symbol @DYNAMIC, essentially the same as *DYNAMIC=$tmp;. @DYNAMIC now aliases @$tmp.

But look at the local. It will restore the list @DYNAMIC, which means it will un-do this binding operation. If going out of scope does a STORE as you show, essentially @DYNAMIC=@saved;, it will overwrite the contents of @$tmp, as opposed to restoring the action of the *DYNAMIC=$tmp;. Follow me? He did not say local *DYNAMIC.

If local worked by pointing the symbol to a new SV, then there would be no need to FETCH/STORE, and the tie would not be preserved.

So there is still more to it than meets the eye.

—John


In reply to Re: (MeowChow - tied local wierdness) Re3: Aliasing Variables by John M. Dlugosz
in thread Aliasing Variables by John M. Dlugosz

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