Path: utzoo!attcan!uunet!bu.edu!snorkelwacker!usc!cs.utexas.edu!helios!cs.tamu.edu
From: skdutta@cs.tamu.edu (Saumen K Dutta)
Newsgroups: comp.unix.wizards
Subject: Re: nested loops
Message-ID: <7318@helios.TAMU.EDU>
Date: 10 Aug 90 06:23:53 GMT
References: <4103@herbie.misemi>
Sender: usenet@helios.TAMU.EDU
Organization: Computer Science Department, Texas A&M University
Lines: 66

In <4103@herbie.misemi> article adley@herbie.misemi writes:   
->
->Hi,
->We are trying to write a Bourne shell script that includes two 
->nested loops as follows
->
->!# /bin/sh
->this="one two three"
->that="four five six seven"
->them="eight nine ten"
->all="this that them"
->#
->for i in $all
->do
->for j in $`echo $i`
->do
->echo $i $j
->done
->done
->
->
->we want (and expected!) the output:
->this one
->this two
->this three
->that four
->that five
->that six
->that seven
->them eight
->them nine
->them ten
->
->The problem lies in the  $`echo $i` statment
->the `echo $i` preforms as expected and the result is one of this,
->that, or them
->the $ infront of this statment however is taken as a literal $
->and does not return the value of the variable this or that or them
->instead it returns $this or $that or $them.
->

If you modify the code in the following way it will work. I bet there
must be a simpler way of doing this:

#! /bin/sh

this="one two three"
that="four five six seven"
them="eight nine ten"
all="this that them"
#
for i in $all
do
k='eval echo $`echo $i`'
for j in `eval $k`
do
echo $i $j 
done
done


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