I was wondering if there was a some sort of predefined alias which would allow access to $_ from one lexical scope down. If it DWIM, it would be named something like $__ (that's dollar-underscore-underscore). Here's an example. Take... 
for my $tmp ("a","b","c")
{
    for (1,2,3)
    {
        print "$tmp, $_\n";
    }
}

[download]
...and get rid of the my $tmp... 
for ("a","b","c")
{
    for (1,2,3)
    {
        print "$__, $_\n";
    }   
}

[download]
And on a related note, is there a way to force a closure to bind particular instances of @_ to its creators @_? Example... 
sub test 
{
    # return a closure to a routine which prints the creator's
    # first argument and the closure's first argument.
    my $val=$_[0];
    sub { print "$val, $_[0]\n" }
}

[download]
...replace with... 
sub test2
{
    sub { print "BLANK $_[0]\n" }
    #              ^
    # fill in the BLANK with something that refers to
    # test2's $_[0], not the anonymous sub's
}

[download]

In reply to $_, one lexical scope removed by sleepingsquirrel

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.