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copied!<pre><code>new_variable=$( awk 'BEGIN{RS=ORS=" "}!a[$0]++' <<<$variable ); </code></pre> <p>Here's how it works:</p> <p>RS (Input Record Separator) is set to a white space so that it treats each fruit in $variable as a record instead of a field. The non-sorting unique magic happens with !a[$0]++. Since awk supports associative arrays, it uses the current record ($0) as the key to the array a[]. If that key has not been seen before, a[$0] evaluates to '0' (awk's default value for unset indices) which is then negated to return TRUE. I then exploit the fact that awk will default to 'print $0' if an expression returns TRUE and no '{ commands }' are given. Finally, a[$0] is then incremented such that this key can no longer return TRUE and thus repeat values are never printed. ORS (Output Record Separator) is set to a space as well to mimic the input format.</p> <p>A less terse version of this command which produces the same output would be the following:</p> <pre><code>awk 'BEGIN{RS=ORS=" "}{ if (a[$0] == 0){ a[$0] += 1; print $0}}' </code></pre> <p>Gotta love awk =)</p> <p><em>EDIT</em></p> <p>If you needed to do this in pure Bash 2.1+, I would suggest this:</p> <pre><code>#!/bin/bash variable="apple lemon papaya avocado lemon grapes papaya apple avocado mango banana" temp="$variable" new_variable="${temp%% *}" while [[ "$temp" != ${new_variable##* } ]]; do temp=${temp//${temp%% *} /} new_variable="$new_variable ${temp%% *}" done echo $new_variable; </code></pre>

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