Hipreme's #1 Tip of the day

Oct 19, 2022

Oct 20, 2022

Hey guys, I'm going to start making a tip of the day (although I'm pretty sure I won't be able to give every day a tip), but those things are really interesting to newcomers to know and may be obvious to some of the old schoolers there.

Always public import a type that the user (including you) is expected to interact with:

Imagine we have a module A that define a tree

module a;
struct Tree(T){}

If you create a module b containing a function that returns a tree:

module b;
import a;
Tree!string getDirectoryTree(string entry){return null;}

This is virtually unusable! One must public import a: Tree;

This will make your API a lot easier to interact with, keep in mind to always public import some type that is used from another dependency like this, but try to not overdo it.

October 19, 2022

Re: Hipreme's #1 Tip of the day

Posted by z
in reply to Hipreme

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Posted in reply to Hipreme

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On Wednesday, 19 October 2022 at 23:28:46 UTC, Hipreme wrote:

Always public import a type that the user (including you) is expected to interact with:

Imagine we have a module A that define a tree

module a;
struct Tree(T){}

If you create a module b containing a function that returns a tree:

module b;
import a;
Tree!string getDirectoryTree(string entry){return null;}

This is virtually unusable! One must public import a: Tree;

This will make your API a lot easier to interact with, keep in mind to always public import some type that is used from another dependency like this, but try to not overdo it.

Will add an important tip for when handling variables of integer type smaller than int :

ushort a, b, c;
c = a + b;//expression a + b will be promoted to int or compiler will emit a deprecation warning
c = cast(ushort) (a + b);//works fine
c = cast(typeof(c)) (a + b);//alternate form
c = cast(ushort) a + b;//bad, only "a" will be casted so you get promoted to int/warned anyway
c += a;//assigning operators' operands won't be promoted, with same types at least
auto d = a + b;//will probably be of type int

note: i didn't 101% check but the above holds true in my usage at least.

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