Declaring a single const: enum vs const vs immutable

[H. S. Teoh]

On Wed, Sep 10, 2025 at 05:15:16PM +0000, monkyyy via Digitalmars-d-learn wrote:
[...]
> I just do always enum; going all in on compile time abstractions

Be careful, this may not always be what you want. For example:

```d
enum data = [ 1, 2, 3 ];

void main() {
	auto buffer = data;	// GC allocation
	...
	auto tmpBuf = data;	// another GC allocation
	...
	assert(buffer is tmpBuf); // fails
}
```

Whereas:

```d
static immutable data = [ 1, 2, 3 ];

void main() {
	auto buffer = data;	// no GC allocation
	...
	auto tmpBuf = data;	// no GC allocation
	...
	assert(buffer is tmpBuf); // true
}
```


T

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