There's a good chance I can make use of str::substr_range on a current project of mine. I'll be storing some substrings from str::split, and now I can store the original string and ranges of indices into it instead of making an owned string for every substring.

[–] TehPers@beehaw.org 4 points 18 hours ago

substr_range is awesome. There's so many times where knowing where in the string the substring is from would have been helpful, especially with parsing. For example, you can calculate where in the input a particular token comes from and even select the full original source that matches a particular pattern by parsing, then calculating what was parsed from the cursor's new position (what's the remainder's range?) and the starting position (what was the range before parsing the pattern?).