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digitalmars.D.learn - use of Class Invariants

reply %u <e ee.com> writes:
At the moment most of my public member functions are littered with these kind
of in-out clauses.

in{
  assert(wellformed, toString);
}
out{
  assert(wellformed, toString);
}

They just beg for invariants, I though..
But invariants don't report the location of failure of contract, only the
location of failure within the invariant.
This seems kind of limiting. Am I missing something here?
Dec 08 2010
next sibling parent reply Jonathan M Davis <jmdavisProg gmx.com> writes:
On Wednesday 08 December 2010 00:22:23 %u wrote:
 At the moment most of my public member functions are littered with these
 kind of in-out clauses.
 
 in{
   assert(wellformed, toString);
 }
 out{
   assert(wellformed, toString);
 }
 
 They just beg for invariants, I though..
 But invariants don't report the location of failure of contract, only the
 location of failure within the invariant.
 This seems kind of limiting. Am I missing something here?

If an invariant fails, it throws an AssertError which will give you stack trace. That stack trace should include which function called the invariant. So, it _does_ tell you which function resulted in the invariant failing. - Jonathan M Davis
Dec 08 2010
parent reply %u <e ee.com> writes:
== Quote from Jonathan M Davis (jmdavisProg gmx.com)'s article
 On Wednesday 08 December 2010 00:22:23 %u wrote:
 At the moment most of my public member functions are littered with these
 kind of in-out clauses.

 in{
   assert(wellformed, toString);
 }
 out{
   assert(wellformed, toString);
 }

 They just beg for invariants, I though..
 But invariants don't report the location of failure of contract, only the
 location of failure within the invariant.
 This seems kind of limiting. Am I missing something here?

That stack trace should include which function called the invariant. So, it _does_ tell you which function resulted in the invariant failing. - Jonathan M Davis

How do I see a stack trace? dmd1(win)
Dec 08 2010
parent Jesse Phillips <jessekphillips+D gmail.com> writes:
%u Wrote:

 That is what I am missing, a stack trace.
 How do I see a stack trace? dmd1(win)

I don't think the Windows stack trace is compete yet. Works in Linux.
Dec 08 2010
prev sibling parent Trass3r <un known.com> writes:
 That is what I am missing, a stack trace.
 How do I see a stack trace? dmd1(win)

Well tango includes stack traces if you import the right module. For D2/Win use http://3d.benjamin-thaut.de/?p=15
Dec 08 2010