How to test if a command is a shell reserved word?

Question

I am writing a bash script and I would like to verify if a string is a shell reserved word (like if, for, alias, etc...).

How can I do this?

Answer 1

#!/bin/bash

string="$1"

if [[ $(type "$string" 2>&1) == "$string is a shell"* ]]; then
    echo "Keyword $string is reserved by shell"
fi