Hello tye,

Thanks for this explanation. When I first read the OP, I completely overlooked the fact that || puts its LHS into scalar context.

However:

... instead of making it match @a = @a || ...

But it doesn’t match!

13:08 >perl -MData::Dump -wE "@a = @a || (1 .. 3); dd \@a;"
[1, 2, 3]

13:08 >perl -MData::Dump -wE "@a ||= (1 .. 3); dd \@a;"
Can't modify array dereference in logical or assignment (||=) at -e li
+ne 1, near ");"
Execution of -e aborted due to compilation errors.

13:09 >perl -v

This is perl 5, version 18, subversion 0 (v5.18.0) built for MSWin32-x
+86-multi-thread-64int

[download]

From the error message, it appears that the ||= operator is putting its LHS into scalar context. Am I correct in reading it this way? If so, it seems strange that perlop#Assignment-Operators doesn’t highlight this important semantic difference between X = X op Y and X op= Y?

Athanasius <°(((>< contra mundum Iustus alius egestas vitae, eros Piratica,

In reply to Re^6: Conditional array initialisation? (scalar, !defined) by Athanasius
in thread Conditional array initialisation? by BrowserUk

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