Create grep command dynamic and run from variable

Question

Hello, I am trying to create regex dynamicly and then run it, this is part of script ...
param="egrep $2 $1"
shift
shift
while [ $# -ne 0 ]
do
param="$param""|egrep $1"
shift
done
$param // here i get error
...
but echo for $param seems to me ok

.P F1 a b c // run script
egrep a F1|egrep b|egrep c

Wha should i do in order to run $param correctly?

Answer 1

try

eval $param

Answer 2

try: eval $cmd

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