# Vectors, boxes and places

**URL:** <https://racket.discourse.group/t/vectors-boxes-and-places/648>\
**Category:** Questions & Answers\
**Created:** [February 4, 2022, 7:42am UTC](https://racket.discourse.group/t/vectors-boxes-and-places/648 "2022-02-04T07:42:19Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![timjervis](https://avatars.discourse-cdn.com/v4/letter/t/45deac/32.png) [@timjervis](https://racket.discourse.group/u/timjervis)\
**Post date:** [February 4, 2022, 7:42am UTC](https://racket.discourse.group/t/vectors-boxes-and-places/648/1 "2022-02-04T07:42:19Z")

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Dear Racketeers,

Is there something I have misunderstood about vectors, boxes and places which might explain why immutable boxes are not place-message-allowed, but immutable vectors are?

```scheme
> (place-message-allowed? (box-immutable #f))
> #f
> (place-message-allowed? (vector-immutable #f))
> #t

```

c.f.

> [4.14&nbsp;Boxes](https://docs.racket-lang.org/reference/boxes.html)
> 
> A box is like a single-element vector, normally used as minimal mutable storage.

Best,

Tim

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<div class="post-metadata">

**Author:** ![mflatt](https://yyz2.discourse-cdn.com/free1/user_avatar/racket.discourse.group/mflatt/32/6_2.png) [@mflatt](https://racket.discourse.group/u/mflatt)\
**Post date:** [February 4, 2022, 2:26pm UTC](https://racket.discourse.group/t/vectors-boxes-and-places/648/2 "2022-02-04T14:26:02Z")

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I don't think there's a deep reason here — probably just that boxes didn't seem useful in a context that disallows mutation, so they were left out. Adding support for boxes would make sense.