So is the following a correct summary of your position as to how you would like things to work?

[ 1, 2, 3];  # a readonly temporary reference to a mutable anonymous a
+rray
[ 1, 2, $x]; # also a readonly temporary reference to a mutable anonym
+ous array

bless 'Foo', [1,2,3];# a readonly temporary reference to a mutable ano
+nymous array
                     # where the array was mutated by blessing it

$a = [1, 2, 3]; # $a is a rw copy of the temp ro array reference
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Dave.

My complaint is primarily about aliases, where I don't understand why Perl complains about when overwriting an alias to 1 but not one to [ 1,2,3,$x] (see examples in my OP especially the update)

Both are literal constructs unbound to any named variable.

I'm NOT saying that anonymous arrays -ie the content - should be immutable, but their reference.

Cheers Rolf
_{(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery}

> So is the following a correct summary of your position as to how you would like things to work?

after rereading it, yes this follows my mental model.

Analog to

1;         # a readonly temporary scalar
$a =  1 ;  # $a is a rw copy of the temp scalar
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Of course I could be wrong, but I'm still waiting for someone to understand my question...

Cheers Rolf
_{(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery}

I'm still waiting for someone to understand my question...

I understand it (I think) :-) The difference between map { $_++ } 1 failing and map { $_++ } [] not failing, or even map { $_++ } \1 not failing, is pretty clear to me. I just don't have an answer for you :-(

With [], I understand the arguments that it's a constructor, for example sub foo () { 1 } can be inlined, but sub bar () { [] } returns a new anonymous array each time. But something like map { $_++ } \undef or map { $_=3 } \1 not failing doesn't entirely make sense to me yet (note map { $$_++ } \undef does fail).

As an aside, I was playing around in the console a bit and can't yet wrap my head around this, it feels buggy, but that may just be because it's getting late here:

$ perl -wMstrict -MData::Dump -e 'dd $_ for map { $_++ } \undef'
\undef
$ perl -wMstrict -MData::Dump -e 'dd $_ for map { ++$_ } \undef'
94067726450329
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Update: Nevermind, it clicked, d'oh. Also made a few minor edits to the above. Update 2: Oops, looks like my update came at just about the same time as your reply, sorry.