assign a string using multiline format

danmcb has asked for the wisdom of the Perl Monks concerning the following question:

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Re: assign a string using multiline format by Taulmarill (Deacon) on Aug 26, 2005 at 11:57 UTC
i'm not shure i understand the question. are you asking for something like this? `# one method my $foo = "sometext\nmore\n"; print $foo; # another method $foo = <<END; sometext more END print $foo;` [download]	[reply] [d/l]
Re^2: assign a string using multiline format by danmcb (Monk) on Aug 26, 2005 at 12:06 UTC
I was looking for the second. I didn't know you could assign with the << operator just like that. cheers.	[reply]
Re: assign a string using multiline format by punkish (Priest) on Aug 26, 2005 at 12:20 UTC
This idiom is called the `HEREDOC`. Think of `<<END; sometext more END` [download] being equivalent to `"$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	[reply] [d/l] [select]
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
Re^4: assign a string using multiline format by chibiryuu (Beadle) on Aug 26, 2005 at 14:54 UTC
Re: assign a string using multiline format by chibiryuu (Beadle) on Aug 26, 2005 at 15:02 UTC
Here-docs are just a convenient way of writing long strings, so (for example) `my_function(<<END, <<END . <<END); a END b END c END` [download] is equivalent to `my_function("a\n", "b\n" . "c\n");` [download] You can of course use different names, i.e. `my_function(<<A, <<B . <<C); a A b B c C` [download] (well, that's not really sensible...) Note that the here-docs must be in order, and start at the end of the line, i.e. `printf <<'END', 1, 2, %d %d %d %d END 3, 4;` [download] prints `1 2 3 4`.	[reply] [d/l] [select]
Re: assign a string using multiline format by chester (Hermit) on Aug 26, 2005 at 13:57 UTC
You don't even need a heredoc in Perl to do this. But this is some mightily ugly code. (Then again, so is the heredoc version.) `use strict; use warnings; my $string = "This is a test..."; print $string;` [download]	[reply] [d/l]