Re: assign a string using multiline format

This idiom is called the HEREDOC. Think of

<<END;
sometext
more
END
[download]

being equivalent to "$var" where $var contains everything between the first line and the last line.

It is interpolated, so any vars inside the HEREDOC is also expanded. So

$foo = 'danmcb';
print <<END;
$foo was here
and here
END
# will print
danmcb was here
and here
[download]

Most wherever you can use $var, you can usually use the HEREDOC. For example

my $text = $cgi->param('text') || <<END;
some text passed via the cgi
END
[download]

works very well. Keep in mind, the trailing END has to be flush with the left most column.

--

when small people start casting long shadows, it is time to go to bed

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Re^2: assign a string using multiline format by reasonablekeith (Deacon) on Aug 26, 2005 at 12:55 UTC
... It is interpolated, so any vars inside the HEREDOC is also expanded it doesn't have to be interpolated, see the following... `print <<'END'; $foo was here and here END # will print $foo was here and here` [download] --- my name's not Keith, and I'm not reasonable.	[reply] [d/l]
Re^3: assign a string using multiline format by danmcb (Monk) on Aug 26, 2005 at 13:17 UTC
why will punkish' HEREDOC interpolate while heith's won't? I don't see the difference ...?	[reply]
Re^4: assign a string using multiline format by Taulmarill (Deacon) on Aug 26, 2005 at 13:28 UTC
heredocs are interpolerated the same way, as the termination string is, so <<EOF is the same as <<"EOF", but <<'EOF' won't be interpolerated. read perldoc perlop -> Regexp Quote-Like Operators -> <<EOF	[reply]
Re^4: assign a string using multiline format by chibiryuu (Beadle) on Aug 26, 2005 at 14:54 UTC
my $foo = 'bar'; print <<END; 1. \$foo is $foo END print <<"END"; 2. \$foo is $foo END print <<'END'; 3. \$foo is $foo END print <<`END`; echo 4. \$foo is $foo END [download] results in `1. $foo is bar 2. $foo is bar 3. \$foo is $foo 4. $foo is bar` [download] See perlop#Quote-and-Quote-like-Operators.	[reply] [d/l] [select]