Perl Best Practices [Electronic resources] نسخه متنی

4.9. Here Documents

Use a heredoc when a multiline string exceeds two lines .

The "break-after-newlines-and-concatenate" approach is fine for a small number of lines, but it starts to become inefficientand uglyfor larger chunks of text.

For multiline strings that exceed two lines, use a heredoc:

$usage = <<"END_USAGE";
Usage: $0 <file> [-full] [-o] [-beans]
Options:
-full  : produce a full dump
-o     : dump in octal
-beans : source is Java
END_USAGE 

instead of:

$usage = "Usage: $0 <file> [-full] [-o] [-beans]\n"
. "Options:\n"
. "    -full  : produce a full dump\n"
. "    -o     : dump in octal\n"
. "    -beans : source is Java\n"
;