How to run script commands from variables?

Question

I tried to run commands using pipes.

Basic:

single=\"ls -l\"
$single

which works as expected

Pipes

Answer 1

when you want to run commands with pipes, just run it. Don't ever put the command into a variable and try to run it. Simply execute it

ls -l |grep

If you want to capture the output, use $()

var=$(ls -l |grep .. )