GC.calloc with random bits causes slowdown, also seen in built in AA

[Michael Rynn]

> 
>> So now the PyDict does not use calloc. and is faster than the built-in.
>> I added a few missing properties (length, opIndex)
> "public size_t size()" is the length you were looking for. Also, opIndex
> might crash if the key is not present. I don't write D2 code., but
> shouldn't opIndex return a pointer to the entry?
   
   Thank you, I needed to improve my understanding the finer details of 
this implementation.
	
// call opIndex, which must return the value type
// may throw exception

   ValueType v = aa[key];    // only works for V opIndex(..)

   ValueType* v = key in aa;	// only works for   V* opIn_r(..)

I should probably continue on this and support all the properties 
mentioned in -

http://www.digitalmars.com/d/2.0/arrays.html#associative

This includes having a .length property.
PyDictD2 is now updated with a .get, and the length() returns the same as 
size().

Also if the aim is to make a drop in replacement for the AA, the
AA should have an implementation available as a struct, (even have the 
same .sizeof) , so it can be placed directly in other structs, local 
variables and classes just like the built-in AA, and no other code will 
have to change.

I am creating a new module based on PyDictD2, to this effect, hope to 
have available ASAP, since it will be mainly refactoring. If I do not 
finish it tonight, it will have to be next week.

When there is such a drop in replacement, it will be easier for others to 
try it out in existing code and uncover quirks and limitations.  Then 
there might be benefits.
-- taf
Michael