Ditto with all the rest of the replies, except... some strange behaviour.
Note that if your undefined variable is 1st in the string, no warning message.
The second print statement does not print a warning.
my $a = 1;
my $b = 2;
my $c = 3;
my $d = 4;
print "$a $b $c $d $e\n";
print "$e $a $b $c $d\n";
My guess is that it is the concatenation of a 'null' that causes the warning.
"$a $b" is optimized to $a." ".$b according to the message I get when I use the 'use diagnostics' with this code.
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:
You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
- a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, 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, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
Link using PerlMonks shortcuts! What shortcuts can I use for linking?
See Writeup Formatting Tips and other pages linked from there for more info.
| & || & |
| < || < |
| > || > |
| [ || [ |
| ] || ] ||