How to dynamically create Bash code with a loop and execute it as it is created I have a list of lines in a Bash script as follows if [ ! -z "$clone01" ]; then git clone "$clone01"; fi if [ ! -z "$clone02" ]; then git clone "$clone02"; fi if [ ! -z "$clone03" ]; then git clone "$clone03"; fi # $clone01 .... through to ... $clone60 if [ ! -z "$clone60" ]; then git clone "$clone60"; fi the leading zero at the end of the variable, when the number is less than 10, is important. I have tried various substitutions and loops etc. This code is very repetitive, and there are 60 lines of it. How can I create this code dynamically and make it part of my executed script? What is the optimal approach to this problem?

Ok, don't do that, it's ugly. Either put the URLs in an array and loop over it:


urls=( )
for url in "${urls[@]}" ; do
git clone "$url"
done


or put them in a file, one per line, and loop reading the lines. Here, it might be useful to guard for empty lines, just like you did. We could also ignore lines starting with `#` as comments:


while read -r url ; do
if [ -z "$url" ] || [ "${url:0:1}" = "#" ]; then continue; fi
git clone "$url"
done < file.with.urls


If you want the line counter too, it's easy to add with arithmetic expansions.