Sizeof class instance

[grauzone]

Justin Johansson wrote:
> grauzone Wrote:
> 
>> Justin Johansson wrote:
>>> How does one determine the sizeof (in bytes) of an instance of a class in D?
>>>
>>> .sizeof works as advertised for structs, but for reference types,
>>> .sizeof yields the sizeof the referencing variable (effectively same as size of a pointer)
>>> and not the size of the underlying instance.
>> As Jarrett said, x.classinfo.init.length is the simplest way in D1.
>>
>>> I did try scanning the NG and read spec_D1.00.pdf.  Perhaps I missed it in the latter.
>> I guess that PDF is horribly outdated, although it may work for some 
>> purposes.
>>
>>> btw. I was poking under the hood of std.xml and though, wow, instances of Element
>>> class look humongous, and so I'm interested to how exactly how humongous.
>> Wasn't std.xml for D2? Anyway, last what I remember is that std.xml is 
>> unmaintained, slow, buggy, and shouldn't be seriously used.
> 
> Yes and yes.  I'm currently using D1 but with view to D2 am having a peek at it's libs.
> 
> I can see why std.xml in D2 is slow, and would not be surprised if buggy as well;  it is quite disgusting code that's been hacked together without any real rhyme or reason.  So guess I'll be writing my own stuff
> and leveraging on C libs where possible.  Got Expat parser running with D without too much trouble.

In case you didn't know, Tango's XML parser is said to be even faster 
than other commonly used XML parsers in C/Java: 
http://dotnot.org/blog/archives/2008/03/10/xml-benchmarks-updated-graphs-with-rapidxml/

Also: http://prowiki.org/wiki4d/wiki.cgi?AllLibraries/XmlLibraries

> Thanks for comment grauzone.
> 
> -- Justin Johansson
>