m|^inline sub (\w+)(.*?^})|sm

inline sub example {
    my ($num, $den) = @_;
    if (! $den) {
        return;
    }
    return $num / $den;
}

##</code><code>##

my $date = calc_date();

inline sub calc_date {
    my $date = strftime('%Y-%m-%d', localtime);
    return $date;
}

##</code><code>##

my $date;
SOMEUNIQUELABEL:
{
    my $date = strftime('%Y-%m-%d', localtime);
    $date = $date;
    last SOMEUNIQUELABEL;
}

##</code><code>##

void_sub($foo, $bar);
my @result = list_context_sub($foo, $bar);
$val = scalar_context_sub($foo, $bar);

##</code><code>##

my ($foo, $bar) = blah($asdf);
# becomes
my ($foo, $bar);

##</code><code>##

my $blah = foo(1, 2);
sub foo {
    my ($var1, $var2) = @_;
    return $var1 + $var2;
}
# becomes
my $blah;
SOMEUNIQUELABEL:
{
    my ($var1, $var2) = @_;
    return $var1 + $var2;
}

##</code><code>##

void - no reference to @_ explicitly or implicitly
my ($var1, $var2) = @_; # consumed all at once, no more references to @_ explicitly or implicitly

##</code><code>##

my $blah = foo(1, 2);
sub foo {
    my ($var1, $var2) = @_;
    return $var1 + $var2;
}
# becomes
my $blah;
SOMEUNIQUELABEL:
{
    my ($var1, $var2) = (1, 2);
    return $var1 + $var2;
}

##</code><code>##

return; # void
return $foo; # single item
return ($blah, $asdf); # multiple items

##</code><code>##

my $blah = foo(1, 2);
sub foo {
    my ($var1, $var2) = @_;
    if ($var2 == 0) {
        return;
    }
    return $var1 + $var2;
}
# becomes
my $blah;
SOMEUNIQUELABEL:
{
    my ($var1, $var2) = (1, 2);
    if ($var2 == 0) {
        $blah = undef;
        last SOMEUNIQUELABEL;
    }
    $blah = $var1 + $var2;
    last SOMEUNIQUELABEL;
}