"strtok" D equivalent

[pascal111]

On Thursday, 28 July 2022 at 20:36:31 UTC, Paul Backus wrote:
> On Thursday, 28 July 2022 at 19:17:26 UTC, pascal111 wrote:
>> What's the "strtok" - C function - D equivalent?
>>
>> https://en.cppreference.com/w/cpp/string/byte/strtok
>
> Closest thing is probably `std.algorithm.splitter` with a 
> predicate:
>
> ```d
> import std.algorithm: splitter, canFind;
> import std.stdio;
>
> void main()
> {
>     string input = "one + two * (three - four)!";
>     string delimiters = "! +- (*)";
>     auto tokens = input.splitter!(c => delimiters.canFind(c));
>     foreach (token; tokens) {
>         writef("\"%s\" ", token);
>     }
> }
> ```
>
> Output:
>
> ```
> "one" "" "" "two" "" "" "" "three" "" "" "four" "" ""
> ```
>
> Unlike `strtok`, this code does not skip over sequences of 
> multiple consecutive delimiters, so you end up with a bunch of 
> empty tokens in the output. To exclude them, you can use 
> `std.algorithm.filter`:
>
> ```d
> import std.algorithm: filter;
> import std.range: empty;
> import std.functional: not;
>
> // ...
>
>     auto tokens = input
>         .splitter!(c => delimiters.canFind(c))
>         .filter!(not!empty);
>
> // ...
> ```

I think "tokens" is a range. I didn't read much about it, but I 
figured out that there's no particular way to know the number of 
elements in a range, or how can you know the elements order and 
the length of the range?