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How can I use a pipe operator in a variable: OPTION="| command"?

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# 1  
Old 05-25-2009
How can I use a pipe operator in a variable: OPTION="| command"?
I have a string of commands I am piping some data through and I want to allow command line switches to select which commands are used. I want to do something like this:
Code:
OPTION="| command3"
command1 -a -b c.txt | command2 -d -e $OPTION >result.txt

I want to do it that way because OPTION may be blank, or may be multiple commands. But it doesn't work.

Is there any way I can make it work?
# 2  
Old 05-25-2009
you can use eval

Code:
OPTION="| command3"
FINALCOMMAND="command1 -a -b c.txt | command2 -d -e $OPTION"

eval $FINALCOMMAND >result.txt

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