Doing exercise from book, but I'm getting error with splitter

[Tolga Cakiroglu via Digitalmars-d-learn]

Add "import std.algorithm". Splitter is defined there.
http://dlang.org/phobos/std_algorithm.html#splitter

On Monday, 16 June 2014 at 16:38:15 UTC, Sanios wrote:
> Hello guys, as first I don't know, if I'm writing to correct
> section, but I've got a problem. I'm actually reading book of D
> guide and trying to do it like it is in book.
>
> My code is:
>
> import std.stdio, std.string;
>
> void main() {
> 	uint[string] dictionary;
> 	foreach (line; stdin.byLine()) {
> 		foreach (word; splitter(strip(line))) {
> 			if (word in dictionary) continue;
> 			auto newID = dictionary.length;
> 			dictionary[word] = newID;
> 			writeln(newID, '\t', word);
> 		}
> 	}
> }
>
> And I'm getting this - Error: undefined identifier splitter
> It seems like std.string doesn't contain splitter.