Eliminate assert and lazy from D?

[language_fan]

Tue, 13 Oct 2009 02:50:11 -0400, bearophile thusly wrote:

> Andrei Alexandrescu Wrote:
> 
>> Usually you're
>> all for adding features (hey, you just brought up the switch again!
>> isn't that ironic?) and cleaning up bad parts of the language,
> 
> Sorry, I'm not a computer scientist, and surely I am not a language
> designer (especially for a C++-class language), so you may see some
> contradictions in what I sometimes say :-)
> 
> I have brought up the switch again because I was nervous, after spending
> some time to find a bug caused by the current design of the switch.
> 
> There are classes of bugs that aren't easy to avoid, but I think with a
> less bug-prone switch I may avoid bugs like the one I have removed from
> my code. One of the most basic part of the Zen of D is to help
> programmers to avoid bugs, where possible.

I thought the priorities were

1) efficient systems programming features
2) metaprogramming fun
3) easy to use (if you come from c/c++)
4) cool new high level features (DbC etc.)
5) other features that make writing bug-free code easier

> I hate the idea of having 3 different switches in the language (that's
> why I was not happy to see the static switch, because a better redesign
> of the *second* switch was in order). But the current situation of
> switch is not good for D yet.

A pattern matching switch which always returns a value, detects unhandled 
cases, matches more than just ints, enums, and strings, does not support 
break and goto, and automatically casts, would be nice.