# Proposal: Bounds checking and removing negative indexing

**URL:** <https://forum.modular.com/t/proposal-bounds-checking-and-removing-negative-indexing/2904>\
**Category:** Mojo\
**Tags:** mojo-proposal\
**Created:** [March 30, 2026, 9:51am UTC](https://forum.modular.com/t/proposal-bounds-checking-and-removing-negative-indexing/2904 "2026-03-30T09:51:25Z")\
**Posts on this page:** 1\
**Page:** 2

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**Author:** ![INsanE-Alchemist](https://sea1.discourse-cdn.com/flex001/user_avatar/forum.modular.com/insane-alchemist/32/224_2.png) [@INsanE-Alchemist](https://forum.modular.com/u/INsanE-Alchemist)\
**Post date:** [May 2, 2026, 8:52am UTC](https://forum.modular.com/t/proposal-bounds-checking-and-removing-negative-indexing/2904/21 "2026-05-02T08:52:38Z")

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So to be clear, it’s not as if the language is removing negative indexing altogether, it’s just that the built in collections will not support them.

Maybe we could have a different collection like a loop, which is like a list but supports indexing in both directions. Then on the “box” put a disclaimer about the performance cost when using in a gpu.

Also at compile time if negative indexes are detected that we get the recommendation to use the other collection which supports negative indexing.

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