Pass range to a function

[Chris via Digitalmars-d-learn]

I'm using regex `matchAll`, and mapping it to get a sequence of 
strings. I then want to pass that sequence to a function. What is 
the general "sequence of strings" type declaration I'd need to 
use?

In C#, it'd be `IEnumerable<string>`. I'd rather not do a 
to-array on the sequence, if possible. (e.g. It'd be nice to just 
pass the lazy sequence into my categorize function.)

What is the value of `???` in the following program:


```
import std.stdio, std.regex, std.string, std.algorithm.iteration;

auto regexToStrSeq(RegexMatch!string toks) {
  return toks.map!(t => t[0].strip());
}

void categorize(??? toks) {
  foreach (t; toks) {
    writeln(t);
  }
}

void main()
{
    auto reg = 
regex("[\\s,]*(~@|[\\[\\]{\\}()'`~^@]|\"(?:\\\\.|[^\\\\\"])*\"|;.*|[^\\s\\[\\]{}('\"`,;)]*)");
    auto line = "(+ 1 (* 2 32))";
    auto baz = matchAll(line, reg);

    categorize(regexToStrSeq(baz).array);
}
```