codecombat / codecombat/codecombat

JavaScript for loops

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Dominant language
JavaScript
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Description

I use JS, and I've noticed that, when for looping through an array, a bug appears if I format my loops like I usually do with other platforms:
var array = []; for (var i in array) { //do something }
I'm not sure as to exactly what happens when I do this, but the game thinks that nothing is wrong (no error messages), but it seems like none of the loops formatted like this actually happen, and any functions I use this in return null values.

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Research direction

Start by reproducing the reported JavaScript for...in loop in the game and trace why the loop body is skipped without an error. Identify the relevant execution entry point, then verify that loops over arrays execute and functions using them return their expected values.

Written by the indexing model from the issue text.

Assessment

Tech stack
javascript
Domain
game-dev
Issue type
Bug
Difficulty
3/5
Estimated time
1-2 days
Activity status
Stale
Clarity
Needs clarification
Newbie friendliness
25/100

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