Why do some T.init evaluate to true while others to false?

[ArturG via Digitalmars-d-learn]

On Friday, 27 May 2016 at 15:24:18 UTC, Adam D. Ruppe wrote:
> On Friday, 27 May 2016 at 15:19:50 UTC, ArturG wrote:
>> yes but i have to check for that when some one does
>
> Why? This is no different than if they set any of the other 
> four billion possible values.

What do you mean?

operation on float.nan gives you a float.nan so why does the 
shortcut evaluate to true and not false wouldnt that make more 
sense?


float f;
if(f) "why does this print".writeln; // it should not

same for char

char c;
if(c) "why does this print".writeln; // it should not

it works for most other types is there any reason why it doesnt 
work or couldnt work with floating points and character types?