=head2 Use of qw(...) as parentheses

Historically the parser fooled itself into thinking that C<qw(...)> literals
were always enclosed in parentheses, and as a result you could sometimes omit
parentheses around them:

    for $x qw(a b c) { ... }

The parser no longer lies to itself in this way.  Wrap the list literal in
parentheses like this:

    for $x (qw(a b c)) { ... }

This is being deprecated because the parentheses in C<for $i (1,2,3) { ... }>
are not part of expression syntax.  They are part of the statement
syntax, with the C<for> statement wanting literal parentheses.
The synthetic parentheses that a C<qw> expression acquired were only
intended to be treated as part of expression syntax.

Note that this does not change the behaviour of cases like:

    use POSIX qw(setlocale localeconv);
    our @EXPORT = qw(foo bar baz);

where parentheses were never required around the expression.