Switch()'s take inputs and let you have cases for single option of the element.  To preform ranges I'm not certain a switch() would be the right idea.  I'm not sure having the 'hacked' switch is any better, or easier to read than:

if ($strength >= 0) return 'weak';
elseif ($strength >= 40) return 'medium';
elseif ($strength >= 80) return 'strong';
elseif ($strength >= 100) return 'perfect';

^^^ is easier to read imo, and doesn't distort what switch() should be doing.

A strict switch operator would be very useful to check for functions that return mixed integers and booleans. Example:

            switch (a_function_that_returns_int_or_bool()) {
                case 2:
                    // do something
                    break;
                case 3:
                    // do something
                    break;
                case true:
                default:
                    // do something
                    break;
            }

This switch statement always evaluates to the first case if the return value of the function is (bool) true. The same happens if you put the "case true" as the first case.

We really need a "strict switch".

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