Pattern: Use of let expr instead of (( expr ))
Issue: -
The (( .. )) arithmetic compound command evaluates expressions in the same way as let, except it's not subject to glob expansion and therefore requires no additional quoting or escaping.
This warning only triggers in Bash/Ksh scripts. In Sh/Dash, neither let nor (( .. )) are defined, but can be simulated with [ $(( expr )) -ne 0 ] to retain exit code, or : $(( expr )) to ignore it.
Example of incorrect code:
let a++Example of correct code:
(( a++ ))