[Swift-devel] [Bug 291] New: Add a exists() function to test for file existence

[Mihael Hategan]

On Sat, 2011-04-02 at 09:00 +0000, Ben Clifford wrote:
> > And I am emphasizing here that the optional attribute should belong to
> > the data. You probably don't want to have it optional with one
> > invocation and non optional with another. Given that the successful
> > completion of a run requires that all invocations complete successfully,
> > anything else would be silly.
> 
> maybe "optional" is not the right word. its data that needs to exist. but 
> you are specifying two ways for it to exist in the scope of the current 
> run: either you find it on a filesystem, or you run some program that 
> outputs it. but I agree that whatever it is called, its attached to the 
> data not to an invocation. it sounds a lot like the virtual data idea.
> 

"maybe"? but that sounds imperative rather than declarative.