On Wednesday, 23 October 2024 at 17:18:47 UTC, Anton Pastukhov
wrote:
On Wednesday, 23 October 2024 at 14:50:44 UTC, Paul Backus
wrote:
You can't use an `alias` to refer to a member variable like
this. When you write
alias myAlias = myStruct.test;
...it is silently rewritten by the compiler to
alias myAlias = MyStruct.test;
So, in reality, there is no difference between the two
versions.
Is it intended behavior? Is it documented somewhere? I'm
looking here https://dlang.org/spec/declaration.html#alias and
it states: "An AliasDeclaration creates a symbol name that
refers to a type or another symbol". `myStruct.test` is a
symbol.
Yes, it's intended.
A "symbol" in D means a named entity declared in the program's
source code. While every instance of `MyStruct` has its own copy
of the `test` member variable, there is only one *declaration* of
`MyStruct.test`--and thus, only one symbol.
In this case, instead of an `alias`, you can use a local function:
```d
MyStruct myStruct;
auto getTest() { return myStruct.test; }
auto idx = countUntil!(e => e == getTest())(...);
```
