Re: Pass range to a function

[Meta via Digitalmars-d-learn]

On Thursday, 27 July 2017 at 21:16:03 UTC, Chris wrote:
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);
}
```

If for some reason you can't make categorize a template like Ali 
suggested, or you need runtime polymorphism, you can use 
std.range.interfaces:

import std.range.interfaces;

void categorize(InputRange!string toks)
{
    foreach (t; toks) {
        writeln(t);
    }
}

void main()
{
    //etc.
    categorize(inputRangeObject(regexToStrSeq(baz)));
}