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6797 :: Instantiation of uint32 type variables only with a maximum value of 2147483647

[2020-09-10T18:11:30+02:00]

BugFix (orginal) [2020-09-10T18:11:30+02:00] view original
I'm a little bit confused. The range of uint32 is 0..4294967295. But it is impossible to assign a variable (uint32) a value larger than 2147483647 in the editor. The Nim project check says instantly: type mismatch: got <int64> but expected 'uint32'. (I'm using VSCodium as editor.) By the other side you can do the following:
```
var test: uint32 = 2147483647
test = 2 * test + 1
echo test         # 4294967295  highest uint32 value
```
It works like expected. So I think, the editor, especially the code ckeck, is the reason. Can someone give a hint, how to solve this problem?

doofenstein (orginal) [2020-09-10T18:22:08+02:00] view original

you need to use 4294967295'u32 to make an unsigned literal

Stefan_Salewski (orginal) [2020-09-10T18:24:17+02:00] view original
Default literals are of int type. Use
```
var i: uint32 = 4294967295.uint32
var j: uint32 = 4294967295'u32

echo i
echo j
```

BugFix (orginal) [2020-09-10T18:34:32+02:00] view original

Wow, very fast answers. Many thanks.

BugFix (orginal) [2020-09-11T09:59:15+02:00] view original
Sorry to ask again. But on one condition:
```
 Default literals are of int type.
```
shouldn't the following assignment be incorrect too?
```
var i: uint32 = 2147483647
```
i is declared as uint32 and is assigned an integer by default. But this is treated as a correct assignment. Is it checked here whether the assigned value matches the range of the declared type and is therefore 'still' valid?

Stefan_Salewski (orginal) [2020-09-11T10:50:46+02:00] view original
```
var i: uint32 = 2147483647

echo i
echo typeof(i)
echo typeof(2147483647)
```
```
$ nim c -r t.nim
2147483647
uint32
int
```
So for this case (non negative int) the compiler does an automatic type conversion. It is compile-time conversion, so no runtime costs. If you don't like it, you may tell Araq.