Normalizing a string and performing Unicode comparisons

We want to make a filename or URL based on an article title. To do this, we'll have to limit the size to an appropriate number of characters, strip out improper characters, and format the string in a consistent way. We also want it to remain in the valid UTF-8 format.

How to do it…

Let's normalize a string by executing the following steps:

1. Use std.uni.normalize to get Unicode characters into a consistent format.

2. Use std.string.toLower to convert everything to lowercase for consistency.

3. Use std.regex to strip out all but a small set of characters.

4. Use std.string.squeeze to collapse consecutive whitespace.

5. Use std.array.replace to change spaces into dashes.

6. Use std.range.take to get the right number of characters, then convert the result back to string.

The code is as follows:

void main(){
  string title = "The D Programming Language: Easy Speed!";
  import std.uni, std.string, std.conv, std.range,std.regex;
  title = normalize(title);
  title...