scope(exit) considered FREAKING AWESOME

Sun Nov 8 11:03:49 PST 2009

downs Wrote:

> auto var = hairilyAllocatedObject();
> scope(exit) cleanupObject(var);
> 
> sock.send("<html><head></head><body>");
> scope(exit) sock.send("</body></html>");
> 
> logln("Digraph D {");
> scope(exit) logln("}");
> 
> SDL_LockSurface(display.surface);
> scope(exit) SDL_UnlockSurface(display.surface);
> 
> auto dg = { performComplexExitCleanupDuty; };
> scope(exit) dg();
> ....
> dg = dg /apply/ (proc dg) { moreCleanup; dg(); };
> ....
> /* Half a dozen different ways of leaving the function go here */
> 
> auto backup = var; var = newValue;
> scope(exit) var = backup;

Yes fine.  You demonstrate the cool use of scope(exit) but
this is a bit like kidding yourself and conscientiously
thinking you didn't *actually* tell a lie because you just
withheld information.

Conspicuous, by the absence of, in your examples is any
use of scope(exit) inside curly-brace scope statements
embedded *inside* a function.

Your examples look fine if one assumes scope(exit) as
relating to function scope.