@dataman, Yours is significantly more readable too. Maybe if you provide a pull-request, plus evidence of correctness, it could be integrated into the standard library.
* [https://github.com/nim-lang/Nim/blob/master/lib/pure/strutils.nim#L1717](https://github.com/nim-lang/Nim/blob/master/lib/pure/strutils.nim#L1717) Meanwhile, @andrea's `memoized` macro is a work of art: * [https://github.com/andreaferretti/memo](https://github.com/andreaferretti/memo) (Memoization is a bit slower than optimized pre-calculation, of course.)
