On Thursday, 21 May 2020 at 02:50:22 UTC, data pulverizer wrote:
I'm a bit puzzled about the whole `@nogc` thing. At first I thought it just switched off the garbage collector and that you had to allocate and free memory manually using `import core.memory: GC;` I tried this and it failed because @nogc means that the function can not allocate/free memory (https://dlang.org/spec/function.html#nogc-functions). If this is the case, how do you allocate/free memory without using the garbage collector? Does allocating and freeing memory using `GC.malloc` and `GC.free` avoid D's garbage collector? Also what is the syntax for removing dangling pointers?
Marking a function @nogc means you can't use the garbage collector in that function, or call other functions that use it. It's still there, and functions that are not marked @nogc can still use it.
To allocate memory without the GC, you have a couple of options. The simplest is to use C's malloc function, which can be found in the core.stdc.stdlib module. A more complicated but more powerful option is to use a non-GC-based memory allocator from the std.experimental.allocator package. Either way, you will have to take care of freeing the memory yourself, either manually or using a technique like RAII.
