Expressing range constraints in CNF form

[Andrei Alexandrescu via Digitalmars-d]

On 6/11/17 3:45 PM, Walter Bright wrote:
> On 6/10/2017 5:28 PM, Andrei Alexandrescu wrote:
>>      && is(typeof(lvalueOf!R.popFront)) && msg("must support back");
> 
> Wouldn't it work better as:
> 
>      && (is(typeof(lvalueOf!R.popFront)) || msg("must support back"));
> 
>      bool msg(string) { return false; }
> 
> ? Then msg() is only called if the first clause fails.

The added parens are a small liability. -- Andrei