Endless loop caused by no warning ()

Question

For reasons completely beyond my understanding, this function works very well:

function foo() {
    var loop = true;
    var abc = ["a","b","c"];
    var ctr = 0;
    while(loop) {
        $("<img />").error(function () {
            loop = false;
        }).attr('src','images/letters/'+abc[1]+(ctr++)+".jpg");
        alert(ctr);
    }
}

But moving alert(ctr)outside whilecauses an endless loop.

function foo2() {
    var loop = true;
    var abc = ["a","b","c"];
    var ctr = 0;
    while(loop) {
        $("<img />").error(function () {
            loop = false;
        }).attr('src','images/letters/'+abc[1]+(ctr++)+".jpg");
    }
    alert(ctr);
}

Can someone help clarify?

Answer 1

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Answer 2

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Answer 3

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Answer 4

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Answer 5

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Is it possible to write a for loop given the length abc?