What's The Story About V's &&char Usage?

[Wajinn]

Why is vlang using &&char and not []string or a conversion from []string to &&char function in bindings? V's doc states its for interoperability, with no elaboration on usage. In the raylib and raygui bindings, for example, other languages use the equivalent of []string in their user facing public functions.

[JalonSolov]

If a reference to a reference to a char is needed, []string in V won't work, because string in V is a struct, not a char * array like in C. An array in V is also a struct, not a simple pointer to a block of memory.

[Wajinn]

Hmmmm... I understand the theory of it, but something is going on with the practical application. Take this situation in the raylib and raygui bindings.

In the raygui (check here), we have a translated function from C.

// vlang version
pub fn gui_list_view_ex(bounds Rectangle, text &&char, count int, scroll_index &int, active &int, focus &int) int

Other bindings (like golang's for example) are able to use their []string equivalent and convert to **char (and additionally the count parameter for the C function). A point that must be noted, is on that project, they look to have done manual touch up and redesigning versus automatic. Anyway, their user facing function has []string.

Why doesn't or should V have a conversion function ([]string to &&char) to make this easier on people or is this looked at as not possible? Is there something about using &&char, where developers think it's a non-issue? Because the practical use, in both golang and C, is to use an array of string and then the array length for the count (rows to display for each string in the array).

//golang version
func ListViewEx(bounds rl.Rectangle, text []string, focus, scrollIndex *int32, active *int32) bool

// original in C
int GuiListViewEx(Rectangle bounds, const char **text, int count, int *scrollIndex, int *active, int *focus)

[Wajinn]

After thinking about it some more and playing around, a viable vlang solution is to use:

array := [c"hello", c"world"] and then cast it &&char(array.data).

array type is []&u8

Only a minor adjustment is needed to get this to work in the translated function used as an example above.

As function example:

fn strchar(arr []string) &&char {
	mut barr := []&u8{} 
	for ele in arr { 
		barr << ele.str
	}
	return &&char(barr.data)
}