Difference between revisions of "Perl"

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(See also: Quotemeta)
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*[http://man7.org/linux/man-pages/man3/strftime.3.html Date formatting symbols]
 
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*[http://perl.com/pub/1999/10/DBI.html Basic DBI tutorial]
 
*[http://perl.com/pub/1999/10/DBI.html Basic DBI tutorial]
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[[Category:Programming languages]]
 
[[Category:Programming languages]]

Revision as of 21:42, 1 April 2016

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Perl one liners

If you type;

perl --help

on the command line, Perl will provide details on its usage and command line switches. The switches we are interested in are

  -d[:debugger]   run program under debugger
  -e program      one line of program (several -e's allowed, omit programfile)
  -n              assume 'while (<>) { ... }' loop around program

Using -e switch

# Unix/Linux
perl -e 'print "It matches\n" if "Hello World" =~ /World/;'
# Windows
perl -e "print \"It matches\n\" if "Hello World" =~ /World/;"
  • See string literals for details on differences between single and double quotes.

Using -de switch

To initiate the debugger for a one line program type;

perl -de 42

Now type 'h' to obtain for help commands used within the debugger. Commands useful for one liners in the debugger are;

  • 'x' to eval an expression in list context, and print the result.
  • 'q' to quit

See also