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[wide_load]

http://www.youtube.com/watch?v=Ph2s7bCN23Q

I think

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1. switch(true){
2.     case ($this === $that):
3.         // stuff
4.     break;
5. }

is unnecessary use of a switch, I don't think its really what they are for.

basically it would work just as well if you remove the switch and replace case with if and else if

switch only makes sense to me when you use some kind of condition in the switch($something) statement...

EDIT: "im not going to wait aroud a year to test it" ... you could have edited the timestamps in the table...

[alex]

I was demonstrating the non-conditional use of switch statements. I'm trying to demonstrate moving away from IF ELSE. Switch statements are also a faster alternative to IF ELSE.

[wide_load]

I was demonstrating the non-conditional use of switch statements. I'm trying to demonstrate moving away from IF ELSE. Switch statements are also a faster alternative to IF ELSE.

are you sure about that ?

surely both methods perform the same logic ?

[alex]

are you sure about that ?

surely both methods perform the same logic ?

They are a faster alternative, yes.

[wide_load]

are you sure about that ?

surely both methods perform the same logic ?

They are a faster alternative, yes.

test script

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1. <?php
2. header('Content-type: text/plain');
3.  
4. $start = microtime(true);
5.  
6. for ($i = 0; $i < 10000000; $i++){
7.     if ('one' == true){
8.         $var = true;
9.     }else if ('this' == 'that'){
10.         $var = true;
11.     }else if (1 == 4){
12.         $var = true;
13.     }else{
14.         $var = false;
15.     }
16. }
17.  
18. echo 'If:     '.(microtime(true) - $start);
19. $start = microtime(true);
20.  
21. for ($i = 0; $i < 10000000; $i++){
22.     switch(true){
23.         case ('one' == true):
24.             $var = true;
25.         break;
26.        
27.         case ('this' == 'that'):
28.             $var = true;
29.         break;
30.        
31.         case (1 == 4):
32.             $var = true;
33.         break;
34.        
35.         default:
36.             $var = false;
37.         break;
38.     }
39. }
40.  
41. echo "\nSwitch: ".(microtime(true) - $start);
42.  
43. ?>

on my server this output

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1. If:     1.699187040329
2. Switch: 2.085853099823

I know its not a very real world test, but it does suggest that switches are not always faster than if else if else ...

comparing the condition next to the case i.e. case (1 == 2) in a switch(true) block is the same as

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1. if ((1 == 2) === true){

which I think may be the reason for the slowness, its doing an extra comparison, the numbers back this up the switch is about 22% slower.

when used the way it is intended the speed difference is much smaller, but still the switch is slower.
test script

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1. <?php
2. header('Content-type: text/plain');
3.  
4. $start = microtime(true);
5.  
6. for ($i = 0; $i < 10000000; $i++){
7.     if ('one' == true){
8.         $var = true;
9.     }else if ('this' == true){
10.         $var = true;
11.     }else if (1 == true){
12.         $var = true;
13.     }else{
14.         $var = false;
15.     }
16. }
17.  
18. echo 'If:     '.(microtime(true) - $start);
19. $start = microtime(true);
20.  
21. for ($i = 0; $i < 10000000; $i++){
22.     switch(true){
23.         case 'one':
24.             $var = true;
25.         break;
26.        
27.         case 'this':
28.             $var = true;
29.         break;
30.        
31.         case 1:
32.             $var = true;
33.         break;
34.        
35.         default:
36.             $var = false;
37.         break;
38.     }
39. }
40.  
41. echo "\nSwitch: ".(microtime(true) - $start);
42.  
43. ?>

on the same server as before this output

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1. If:     1.6776959896088
2. Switch: 1.9025719165802

again, i know this is not a real world example, but it does show that the switch is slower, and must be doing more comparison when used in the way (which i believe to be incorrect) you do in the video.

hopefully you will be able to explain this.

[alex]

Try the two statements but in two different files.

[wide_load]

Try the two statements but in two different files.

that made no difference at all.

I don't see why it would do