Idiomatic way to test if no positional params are given?

Question

What is the most idiomatic way in Bash to test if no positional parameters are given? There are so many ways to check this, I wonder if there is one preferred way.

S

Answer 1

Here's a most logical way:

[ ! $@ ]

It is based on a single rule:

[ ] # this returns 1

Well then,

[ ! ] # this returns 0

The rest is obvious: $@ is the special parameter that expands to a list of all positional parameters.

Test: (It will work even if you throw a couple of empty strings ("" "" "") at it.)

if [ ! $@ ]; then
    printf 'Note: No arguments are given.'
fi