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Full Discussion: Eval command help
Top Forums Shell Programming and Scripting Eval command help Post 302472156 by nikhilfake on Tuesday 16th of November 2010 12:07:42 PM
Old 11-16-2010
Eval command help

I have file called myfile which has the text "myserver" in it. I need to have a command to ping "myserver". How would I do that?

I tried
Quote:
myvar= 'cat myfile'
when I type
Quote:
"eval $myvar"
at the terminal I get the output as
Quote:
"myserver"
. How do I do something like a
Quote:
ping "eval $myvar"
?

thanks,
Nick
 

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Padre::Task::Eval(3pm)					User Contributed Perl Documentation				    Padre::Task::Eval(3pm)

NAME
Padre::Task::Eval - Task for executing arbitrary code via a string eval SYNOPSIS
my $task = Padre::Task::Eval->new( prepare => '1 + 1', run => 'my $foo = sub { 2 + 3 }; $foo->();', finish => '$_[0]->{prepare}', ); $task->prepare; $task->run; $task->finish; DESCRIPTION
Padre::Task::Eval is a stub class used to implement testing and other miscellaneous functionality. It takes three named string parameters matching each of the three execution phases. When each phase of the task is run, the string will be eval'ed and the result will be stored in the same has key as the source string. If the key does not exist at all, nothing will be executed for that phase. Regardless of the execution result (or the non-execution of the phase) each phase will always return true. However, if the string eval throws an exception it will escape the task object (although when run properly inside of a task handle it should be caught by the handle). METHODS
This class contains now additional methods beyond the defaults provided by the Padre::Task API. COPYRIGHT &; LICENSE Copyright 2008-2012 The Padre development team as listed in Padre.pm. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. The full text of the license can be found in the LICENSE file included with this module. perl v5.14.2 2012-06-27 Padre::Task::Eval(3pm)
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