On Wed, 1 Jul 2009, Tom Verhoeff wrote:
On Tue, Jun 30, 2009 at 07:58:47PM +0100, Inoussa OUEDRAOGO wrote:
2009/6/29 Tom Verhoeff <t.verho...@tue.nl>:
While tracing a nasty bug (?), I discovered the hard way that when
an Assert is done in a constructor, and it fails, then the destructor
(Destroy) is automatically called.
Indeed, when an exception is raised in the constructor, be it an
"assert" exception or not, the destructor is called to allow the
developer to clean up the "in-construction" instance's members he has
already initialized.
A colleague of mine pointed out that the Delphi 7 documentation for
TObject.Create actually says so (see final Note):
Constructs an object and initializes its data before the object is first
used.
Delphi syntax:
constructor Create;
Description
Create constructs an object. The purpose, size, and behavior of objects
differ greatly. The Create constructor defined by TObject allocates memory
but does not initialize data.
Descendant objects usually define a constructor that creates the
particular kind of object and initializes its data.
Note: If an exception escapes from a constructor, the object's
destructor is called to clean up the failed instance.
Zoiets zou ook in de TObject.Create (RTL) doc. van FreePascal passen
(lees: thuishoren).
For non-dutch speakers: It says that this kind of information should
be included in the FPC documentation. I will do so. But in my opinion,
it does not belong in the unit reference documentation, but in the language
documentation.
Michael.
_______________________________________________
fpc-pascal maillist - fpc-pascal@lists.freepascal.org
http://lists.freepascal.org/mailman/listinfo/fpc-pascal
