On 19.02.2013 17:49, Mark Morgan Lloyd wrote:
Sven Barth wrote:
OK, so is it possible to set up a constant extended record (i.e. the
work being done entirely at compilation time) that mimics an
instantiated object? Would
if LibCapShim is TObject then
..
be safe where LibCapShim could be either an object (possibly nil) or a
constant extended record?
You could try to overload the "is" operator for your to be defined
static record [AFAIK it should work]. E.g.
=== code begin ===
TLibCapShim = record
cap_get_proc: tcap_get_proc;
// ...
class operator is (aLeft: TLibCapShim; aRight: TClass): Boolean;
inline;
end;
class operator TLibCapShim.Is(aLeft: TLibCapShim; aRight: TClass):
Boolean;
begin
Result := False;
end;
=== code end ===
Thanks Sven, looks interesting and I'll play with it presently. Can an
extended record's fields/methods be set up at compilation time, or do
they need to be done by code?
The example I've given was for the case that you load the functions
dynamically and use the procvars contained in the record. You could do
it this way as well:
=== code begin ===
TLibCapShim = record
function cap_get_proc: tcaps;
end;
//...
function TLibCapShim.cap_get_proc: tcaps;
begin
Result := UnitContainingImports.cap_get_proc;
end;
=== code end ===
You need to pay attention to call the correct functions, of course.
Regards,
Sven
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