print "print "$n1 plus $n2 is ", $n1 + $n2, "\n";

where $n1 and $n2 are integers pulled from STDIN and chomped, outputs "4 plus 2 is 6" like it's supposed to.

However, what I tried to use before:

print "$n1 plus $n2 is " . $n1 + $n2 . "\n";

returns

Argument "4 plus 2 is 4" isn't numeric in addition (+) at operators.pl line 10, <STDIN> line 2.

but then goes on running the script. This is a warning, I assume, as it doesn't appear when I remove the warning flag from my hashbang line.

Also, this only outputs 6 as opposed to 4 plus 2 is 6.

Why does it behave this way?
It's not a huge deal as I've got it doing what I want now, but I'm curious.


In reply to This is odd. by JDelmoso

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.