Local variable to global variable in JS for loop, value changed after loop ends [duplicate]

Question

Curious about why i becomes 5 in the end?

for (var i = 0; i < 5; i++) {
  console.log('A: ', i);
}
console.log('B: ', i);

i = 4 -> i < 5 === true -> console.log('A: ', i); -> i++ -> i = 5 -> i < 5 === false -> end loop. — VLAZ
– VLAZ, Commented Jun 23, 2020 at 9:09
var i gets hoisted. It's equivalent to var i; for(i=0;i<5;i++) console.log(i); console.log(i) — user120242
– user120242, Commented Jun 23, 2020 at 9:09
because at end it becames 5 and the condition becomes false and it breaks and console.log B where I = 5 — xMayank
– xMayank, Commented Jun 23, 2020 at 9:10
@NinaScholz How do you guys find these dupes? Makes me feel like I don't know how to use Google anymore — user120242
– user120242, Commented Jun 23, 2020 at 9:12

Quentin · Accepted Answer · 2020-06-23 09:09:53Z

3

i++ increases the value of i at the end of each loop.

The loop goes round until the condition (that i is 4 or less) isn't true.

When i is 5, that is the first time the condition isn't true.

answered Jun 23, 2020 at 9:09

Quentin

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