default as first option in switch statement?

Question

I\'ve tested this and it works fine, but it looks... weird... to me. Should I be concerned that this is nonstandard form which will be dropped in a future version of PHP, or

Answer 1

Other answers give good examples of it, just stating for clarity's sake...

A Case (including default) does not stop executing at its end unless you include a break. Although switch is often compared to a sequence of if elseif elseif etc., however it's not quite that.

Short version: SWITCH/CASE only acts like IF/ELSEIF/ELSE if you include breaks after each case. SWITCH/CASE is more like a series of "if" statements where each has the same variable check with a different value it's being checked against.

Long version: Without including a break, each case is a "start here"and the differences in a lot of ways make it closer to GOTO without the drawbacks. Technically, if you really REALLY wanted to (read, were a masochistic coder who wanted to really challenge themselves) you could write almost any procedural programs using only one external array, a for loop, and a switch nested inside.

Seriously, why you would want to do this boggles my mind, but it really demonstrates how far switch/case can deviate from if/elseif patterns, so it's here for you for academic reasons (but don't do it!)...

$array = [];
$array['masterLoop'] = 1;
$for ($i = 0, $i < $array['masterLoop'], $i++ ){
    switch($array['goto']){
        default: 
        case 1: 
            PRINT: "Welcome to the program";
        case 2: 
            PRINT: "Please make a choice:";
        case 3:
            $array['choice']='';
            // Wait for some input variable and set choice to it.
        case 4: 
            $array['goto']=$array['choice'];
            $array['masterLoop']++;
    }
}

The way this code would run (after you set up something for capturing and setting a choice) would be it'd start up with

"Welcome to the program. Please make a choice."
<>
"Please make a choice."
<>
"Welcome to the program. Please make a choice."
<>
// program awaits user input
<>
// user triggers infinite loop

So... you can use switches to reflect back to the days of BASIC... but if you do and I have to debug your code later after you wrote it all like that... May Linus Torvalds mercy on your soul.