What does while (i --> 0) mean?

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不思量自难忘°
不思量自难忘° 2020-12-17 02:29

I apologize if this a stupid question, but I cannot find the answer anywhere.

How does the following code work? (I realize that it loops over the elements of e

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  • 2020-12-17 03:01

    It should be read as

    i-- > 0
    

    So, what really happens is,

    1. value of i will be checked if it greater than 0, if it is true then control will enter the while block, if it is false while block will be skipped.

    2. Either way, the value of i will be decremented, immediately after the condition is checked.

    Its always better to use for loop, when we run a loop with a counter, like this

    for (var i = els.length - 1; i >= 0; i -= 1) {
        ...
    }
    

    Please read more about whether ++, -- is okay or not.

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  • 2020-12-17 03:09

    It's just weird spacing. It's same as

    while (i--  >  0) {
    
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  • 2020-12-17 03:16

    It's just weird spacing, should be

    while((i--) > 0)
    

    it's just post-decrementing and checking the condition. There was this humorous answer at the C++ question, but I think it got deleted

    while (x --\
                \
                 \
                  \
                   > 0) //i goes down to zero!
    

    Or something like that, anyway

    So if you had something like

    var i=3;
    while(i-->0){
         console.log(i);
    }
    

    it would return

    2
    1
    0
    
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  • 2020-12-17 03:17

    The code should actually be:

    while (i-- > 0) {
    

    where the loop will run if the value after the variable i has been decremented is greater than zero.

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