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A somewhat non obvious scoping issue of javascripts callbacks
function test() {
for (var i=0;i < 5;i++) {
console.log('orig: '+ i);
// Crazy function with a callback here, making it async
setTimeout(function () {
// We might expect `i` to be whatever it was in the loop
// when we called the setTimeout, but it's actually not evaluated
// until the "callback" runs, and hence it will have the value
// `i` had in that exact moment.
console.log('cb: '+ i);
}, 100);
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