Re: U : Unbounded_String := "bla bla bla"; (was: Is the Writing...)

["Mark A. Biggar" <mark@biggar.org>]

amado.alves wrote:

> "...we already have implicit conversion in Ada for numeric literals." (Jeff)
> 
> I know, and that was the 'precedent' for my proposal. And I'm familiar with the 'nightmare' of generalised implicit conversion (in C). But this could be tamed in Ada by defining the effect scope of pragma Implicit_Conversion to be the immediately enclosing block.
> 
> Or a family of such pragmas for fine control of the effect:
> 
>   Implicit_Conversion_Down_From_Here
>   Implicit_Conversion_Up_To_The_Next_Enclosing_Block
>   Implicit_Conversion_All_Over
> 
> However I am not totally confortable with *pragmas* for this class of effect. Is their precedence?

The ARG would probably reject these pragmas out of hand.  There are
currently no pragmas that take a syntatically illegal program and make
it legal, which is what the above do (actually pragma import is an 
exception to this rule, but it fills in missing syntax, not changes 
illegal to legal).  It's alright to make legal things illegal (E.g.,
pragme restrictions) but not the other way.  See LRM 2.8(16)

-- 
mark@biggar.org
mark.a.biggar@comcast.net