Delphi Compiler Error
E2207 ‘%s’ clause not allowed in interface type
Reason for the Error & Solution
The clause noted in the message is not allowed in an interface type. Typically this error indicates that an illegal directive has been specified for a property field in the interface.
program Produce; type Base = interface function Reader : Integer; procedure Writer(a : Integer); property Value : Integer read Reader write Writer stored false; end; begin end.
The problem in the above program is that the stored directive is not allowed in interface types.
program Solve; type Base = interface function Reader : Integer; procedure Writer(a : Integer); property Value : Integer read Reader write Writer; end; begin end.
The solution to problems of this nature are to remove the offending directive. Of course, it is best to understand the desired behavior and to implement it in some other fashion.