A happy, successful and healthy New Year to everybody!
I have a generics related compilation issue in my package ExCtrls
package
(https://sourceforge.net/p/lazarus-ccr/svn/HEAD/tree/components/exctrls/).
This package contains a TCurrencySpinEditEx component which inherits
from the TSpinEditExBase component of the LazControls package coming
with Lazarus. TSpinEditExBase introduces generic fields FValue,
FIncrement, FMaxValue etc, and each decendent of it specializes these
types, i.e. in TCustomFloatSpinEditEx FValue, FIncrement, FMaxValue are
double, and in the CurrencySpinEdit for the ExCtrls package they are
currency values.
The compilation of the ExCtrls package fails for example in the
IncrementStored method of TSpinEditExBase
function TSpinEditExBase.IncrementStored: Boolean;
begin
Result := not SameValue(FIncrement, DefIncrement); // <---
error here; SameValue is from unit Math
end;
the error message says: "Can't determine which overloaded function to
call". FIncrement and DefIncrement are generic types here.
What is strange to me is that the compilation issue does not happen with
the LazControls package alone, but only when ExCtrls package is added.
Moreover, the problem occurs only on 64bit, not on 32 bit. (I am on Windows)
I can solve the compilation issue by moving the IncrementStored method
into the derived classes. But this kind of contradicts the idea with
using generic types in the first place.
Is there another way to solve this issue?
Werner
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