Re: Does 'ref' turn into a pointer during compile time?
On 12/21/22 16:43, thebluepandabear wrote:
> Say you have the following function that takes in a `ref` parameter:
>
> ```D
> void modify(ref int num) {
> num += 5;
> }
> ```
>
> Does the compiler turn that into the code below?
>
> ```D
> void modify(int* num) {
> num += 5;
Rather:
*num += 5;
> }
> ```
>
> I was just wondering whether or not this is the case because I don't
> think this was touched in the book about D I am reading.
Yes, references are realized by pointers by CPUs; so that's how the code
is compiled as well.
Pointers are considered to be one of the most difficult concepts for
beginners (who the book was supposed to target). That's why I tried to
hold it off as much as possible. I think once the concept of a reference
is understood, pointers should be easy to understand.
That's why I say "Behind the scenes, D's higher-level concepts (class
variables, slices, associative arrays, etc.) are all implemented by
pointers." only later in the book on the pointers page:
http://ddili.org/ders/d.en/pointers.html
Ali
Re: in dub single file build how to pass "-J" options?
stringImportPaths
Re: in dub single file build how to pass "-J" options?
On Thursday, 22 December 2022 at 02:19:23 UTC, mw wrote: I have example.d: ``` #!/usr/bin/env dub /+dub.sdl: dependency "tkd" version="~>1.1.14" +/ ... ``` $ dub build --single example.d ... Error: need `-J` switch to import text file `folder_page.png` I'm wondering how to pass "-J" options? Found it, it's: ``` /+dub.sdl: dependency "tkd" version="~>1.1.14" dflags "-Jmedia" +/ ``` BTW, for such single file build, do I have to use dub? is there another way to just use dmd? Still don't know how to directly invoke dmd to build.
in dub single file build how to pass "-J" options?
I have example.d: ``` #!/usr/bin/env dub /+dub.sdl: dependency "tkd" version="~>1.1.14" +/ ... ``` $ dub build --single example.d ... Error: need `-J` switch to import text file `folder_page.png` I'm wondering how to pass "-J" options? BTW, for such single file build, do I have to use dub? is there another way to just use dmd? Thanks.
Re: Does 'ref' turn into a pointer during compile time?
On Thu, Dec 22, 2022 at 12:43:28AM +, thebluepandabear via
Digitalmars-d-learn wrote:
> Say you have the following function that takes in a `ref` parameter:
>
> ```D
> void modify(ref int num) {
> num += 5;
> }
> ```
>
> Does the compiler turn that into the code below?
>
> ```D
> void modify(int* num) {
> num += 5;
> }
> ```
>
> I was just wondering whether or not this is the case because I don't
> think this was touched in the book about D I am reading.
Yes, a ref parameter is implemented as a pointer in the generated
assembly code. But that's supposed to be an implementation detail that
you generally shouldn't worry about unless you're working with low-level
operations.
T
--
Ph.D. = Permanent head Damage
Does 'ref' turn into a pointer during compile time?
Say you have the following function that takes in a `ref`
parameter:
```D
void modify(ref int num) {
num += 5;
}
```
Does the compiler turn that into the code below?
```D
void modify(int* num) {
num += 5;
}
```
I was just wondering whether or not this is the case because I
don't think this was touched in the book about D I am reading.
