Date: Sat, 04 Jul 2020 12:30:54 -0500
From: Westerbly Snaydley <westerbly@gmail.com>
Subject: Re: unexpected behavior with arrays?
To: Shawn Walker <binarycrusader@gmail.com>
Cc: ~duangle/scopes@lists.sr.ht
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	<CAAhSavZq+TFWtwg1+V_XC5W9cED8SFyzeqf1Na1LnzsePL5_XA@mail.gmail.com>
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On Fri, Jul 3, 2020 at 22:45, Shawn Walker <binarycrusader@gmail.com>=20
wrote:
> $0 =E2=96=BA x @ 0
> $0 =3D 0

TL;DR: you have a stale stack pointer.

As you probably know, `alloca`'d pointers are not meant to survive=20
beyond the function frame, and the way the REPL works is that it wraps=20
every evaluated expression in a function; the result of this is that=20
it's impossible to keep function-local pointers valid between=20
evaluations. What you may do is use a global array instead, or even one=20
using the `local` keyword since that was improved recently to work=20
better in this situation. Your code will work like this:

```
$0 =E2=96=BA local x : (array i32 5)
(arrayof i32 0 0 0 0 0)
$0 =E2=96=BA x @ 0 =3D 1
$0 =E2=96=BA x @ 1 =3D x @ 0 + 1
$0 =E2=96=BA x @ 0
$0 =3D 1
$1 =E2=96=BA x @ 1
$1 =3D 2
```

Westerbly (radgeRayden) Snaydley.