On Tue, 19 Oct 2010, Sven Barth wrote:

Am 19.10.2010 19:54, schrieb Juha Manninen (gmail):
On Tuesday 19 October 2010 19:10:39 Luiz Americo Pereira Camara wrote:
Yes it's ready in fpc 240:

uses
   Fgl;

type
   TIntegerList = specialize TFPGList<Integer>;

Well, yes. It is almost as good as a dedicated class. It has a Sort method but
you must feed the compare function for it.
It does not have a Find method for a binary search in a sorted list.
Indexof does a linear search.

Anyway, it could be used as a base class in Lazarus. I don't know what is the
Lazarus team's policy for using generics in Lazarus code-base.

In FPC 2.4.0 I had problems with memory consumption of generics containers.
A<Integer, Integer>  map hogged gigabytes of memory while my data took only
kilobytes (less than 1 MB for sure), on a 64 bit Linux.
Now I have the latest FPC trunk 2.5.1 and the problems are gone. I added
100000 integers to both a List and to a Map and didn't even notice the memory
increase in resource monitor.

   TIntegerList = specialize TFPGList<Integer>;
   TIntegerMap = specialize TFPGMap<Integer, Integer>;

TFPGMap's problem still is that it is not a hash map and is butt-slow with
lots of data. A hash map is a superior container type, it really should be
changed.
Besides, people expect to get a hash map when they see "map" in the class
name. Now they get a list which is deceivingly named as "map".

As you seem to have experience with efficient data structures, what about creating such a generic hash map? :)

(but don't use 2.4.2rc1 and current/unpatched 2.4.3 as a test base as those don't have the fixes from trunk to make "specialize" working again)

Currently, the FPC team is looking at an implementation of Vlado Boza <us...@ksp.sk> for a standard template library for inclusion in FPC.

The code is on

http://code.google.com/p/stlpascal

Please have a look and comment on it.

I'm not a generics expert and am not in the position to judge whether this 
library is good or not.

Michael.
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