On 03/05/2010 10:58, spir ☣ wrote:
Hello,A few questions on the topic: * Is it possible to define an optional parameter without default value? * Is it at all possible for an optional *argument* not to be the last in actual call? Eg procedure p(a:Integer=0 ; b:Integer=0) How can the caller pass b and not a? * The ref states: "For dynamic arrays or other types that can be considered as equivalent to a pointer, the only possible default value is Nil." Does this apply to any non-atomic type? Which are the "other types that can be considered as equivalent to a pointer"? Tried with a record, but cannot make it be accepted by the compiler. Needed to change the parameter to be a pointer to the record instead (so the default can be nil), but this creates a trap for the calling code. Else, is there a common trick or workaround?
Maybe you want to use overloading instead of optioanl parameters? Procedure Foo; overload; // no params Procedure Foo(SomeRecord: TRecordType); overload; // no params then of course you need to implement twice Procedure Foo; var a: TRecordType; begin a:= xxx;/your defaults Foo(a); end; Procedure Foo(SomeRecord: TRecordType); begin / do work end; _______________________________________________ fpc-pascal maillist - fpc-pascal@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-pascal
