Hi, M. Lewis <[EMAIL PROTECTED]> asked: > You've lost me here Thomas. Again, his code was: > > open my $fh, '<', $input_file or die qq(Cannot open > "$input_file": $!); > > What am I missing here?
Charles wants to output an error message like Cannot open "somefilename": No such file or directory at somescript line xx. The part behind the colon is the error message in $!. The naive way to construct this print would be to write print 'Cannot open"' . $input_file . '":' . $!; This is horrible, since Perl can interpolate variable names in strings quoted using double quotes. However, if you want to use the double quote character inside of such a string, you have to escape that character in order to distinguish it from a string ending quote: print "Cannot open \"$input_file\": $!"; This is where the qq() operator comes in. It basically acts like a double quote for its contents, without actually using that character - so you can now have a string that can be interpolated but in which the doubles quotes do not have to be escaped: print qq(Look Ma! No "backslash"!); And if you wanted to use round brackets inside your string, you could use a different set of delimiters, like so: print qq/Again, no escape character required for "()"/; See the perlop manpage for details, and qq's useful relatives q, qr and qw. HTH, Thomas -- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] <http://learn.perl.org/> <http://learn.perl.org/first-response>
