So write some code that modifies a "list". What would that be?

We're still waiting for you to show it's possible.

Some authors say that @xyz is a list and that xyz is an array variable that defines a list.

So far, I've only seen you, and that's the problem.

What's wrong with saying that @xyz is a list?

It's very confusing. It leads to contradictory statements. If we went by your definition, all of the following statements are true depending on whether you are talking about (foo,bar) or @foo.

• A list can't be modified.
• A list can be modified.
• A list in scalar context evaluates to its last item.
• A list in scalar context evaluates to the number of elements it contains.
• Nested lists are flattened into a single list.
• Nested lists aren't flattened into a single list.

[What's wrong with saying] that xyz in the context of @ is a list?

Now you want to redefine "context" too! What do you have against being understood.

[What's wrong with saying] that (@xyz >1) is a list in a scalar context?

You wouldn't be talking about Perl. In Perl, lists evaluate to their last element in scalar context.

print(scalar( ( 'a', 'b', 'c' ) ));   # c
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However, @xyz does not.

@xyz = ( 'a', 'b', 'c' );
print(scalar( @xyz              ));   # 3
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