|Posted by Paul Backus|
in reply to Ruby The Roobster
Posted in reply to Ruby The Roobster
On Tuesday, 29 September 2020 at 01:46:56 UTC, Ruby The Roobster wrote:
> I thought alias could work like this with classes:
> alias test = MyClass(3,"H",9.1); //Assume the constructor parameters for MyClass are (int,string,double).
> Can anybody fix this code?
`alias` lets you create a new name for an entity that already exists somewhere in your program.
The "entity" in question can be a lot of different things--a type, a variable, a function, a module, a template--but it must be something that exists independently of the alias. In other words, you cannot use `alias` to give a name to something that does not already have one.
But wait, you might ask, if that's true, how can you alias a lambda? It's an anonymous function; by definition, it doesn't have a name!
alias increment = (int x) => x + 1;
The thing is...lambdas actually do have names. They're just generated internally by the compiler. You can't actually *use* them in your code, but they do occasionally show up in error messages:
// Error: function literal `__lambda1(int x)` is not callable using argument types `(string)`