Using the -p option on the command line
Topicalization and Special Variables example from a Well House Consultants training course
More on Topicalization and Special Variables [link]
Source code: perltodiamond Module: P210
=head1 Using the -p option on the command line
Perl's -p command line option adds an implicit
loop around your program, with each line being
read in turn from the file named on the command
line into $_ (the default input and pattern
matching space) and then, after the code has been
run, printing out $_.
In this example, we're changing all Perls to
Diamonds, then moving all vowels one vowel up the
File started like this:
antonia Perl XML PHP Knitting MySQL
barbara Tcl/Tk Lua Ruby Java
cherry Perl Java Ruby MySQL
delia XML PHP Java Lua
ethel MySQL Perl Tcl/Tk Lua
florence Ruby Lua PHP Java
gloria XML Perl Tcl/Tk MySQL
hazel PHP Python Perl Ruby Lua
iris Perl MySQL Java Tcl/Tk
Results like this:
entunoe Doemund XML PHP Knottong MySQL
berbere Tcl/Tk Lae Raby Jeve
chirry Doemund Jeve Raby MySQL
diloe XML PHP Jeve Lae
ithil MySQL Doemund Tcl/Tk Lae
flurinci Raby Lae PHP Jeve
gluroe XML Doemund Tcl/Tk MySQL
hezil PHP Pythun Doemund Raby Lae
oros Doemund MySQL Jeve Tcl/Tk
Learn about this subject
This module and example are covered on the following public courses:
* Perl Programming
* Perl bootcamp
* Learning to program in Perl
* Perl Programming
Also available on on site courses for larger groups
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This example comes from our "Topicalization and Special Variables" training module. You'll find a description of the topic and some other closely related examples on the "Topicalization and Special Variables" module index page.
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