Re: memory management in Ada: tedious without GC?

[Pascal Obry <pascal@obry.net>]

Bob Klungle a �crit :
> "Pascal Obry" <pascal@obry.net> wrote in message 
> news:482E8A9D.5040401@obry.net...
>> jhc0033@gmail.com a �crit :
>>> Did I misunderstand?
>> You have already received a bunch of excellent answers. I'd like to point 
>> out that in Ada you have less need for dynamically allocated memory. Ada 
>> supports unconstraint types. Objects of such types when declared can be 
>> "allocated" on the stack and passed around (no heap usage). A simple 
>> example:
>>
>>    type Vector is (Positive range <>) of Float;
>>
>>    function Norm (V : in Vector) return Float;
>>
>>    ...
>>
>>    declare
>>       V : Vector (1 .. 100);
>>       R : Float;
>>    begin
>>       R := Norm (V);
>>       ...
>>
>> Not a single memory allocation. In C/C++ you'll need to dynamically 
>> allocate V on the heap, and then worry about freeing this memory.
>>
>> Pascal.
> 
> Actually, the same construct exists in c/c++.

Ok, I meant a non statically known constraint. My example was not 
accurate enough then.

    type Vector is (Positive range <>) of Float;

    function Norm (V : in Vector) return Float;

    ...

    N := <runtime computed value>;

    declare
       V : Vector (1 .. N);
       R : Float;
    begin
       R := Norm (V);
       ...

> Stack frame allocation only needs a block to allow object definitions (c++ 
> does it almost anywhere).

And for anything else when the size of the object is not known at 
compile time. That's why I talked specifically about unconstraint objects.

Pascal.

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