RFC: Value range propagation for if-else

[bearophile via Digitalmars-d]

Lionello Lunesu:

> Have a look at the branch:
> https://github.com/lionello/dmd/compare/if-else-range

The need for this D improvement is sufficiently common, a just 
appeared question:
http://forum.dlang.org/thread/jwfvuaohvlvwzjlmztsj@forum.dlang.org

Lionello needs some cheering & support to create the patch that 
implements the value range propagation for if-else. Exposing the 
range and implementing value range propagation for if-else are 
sufficiently distinct needs.

Bye,
bearophile