scope exception do not rise

[Suliman via Digitalmars-d-learn]

> We have to look at the documentation of the function. In this 
> case the possibilities are FileException and UTFException.
>
>   http://dlang.org/phobos/std_file.html#.readText
>
> However, judging by their names, they are both descendants of 
> Exception, so what you are doing will catch either of them.
>

Where I can look at hierarchy of exceptions?