Hi,

You can try it! 

$ perl -Mstrict -wE '$_ = q{foo}; $_ = qq~"$_"~; say $_'
"foo"

[download]
It's forcing the string to include leading and trailing double quotations marks as part of the string. The use of the tilde character to define the start and end of what's passed to qq) is just a style choice and doesn't affect the code. (Also, the use of qq in the code you posted is unnecessary: $_ = '"$_"'; would have done the same thing. See also Quotes and Quote-Like Operators)

In this case, the code is doing so if the string contains a comma, so it is undoubtedly a misguided attempt to manually escape values in a delimited file. You should never attempt to do that yourself, as it's more complicated that it might seem. Instead, use a module designed for handling delimited files, such as Text::CSV.

Hope this helps!


The way forward always starts with a minimal test.

In reply to Re: What does $_ = qq~"$_"~ do? by 1nickt
in thread What does $_ = qq~"$_"~ do? by mkj

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.