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Aleksandar Donev writes: > The books I have say that argument keywords must be provided in > interfaces, as in: > > interface > subroutine test(first=a) > real, intent(in) :: a > end interface > > but also that explicit interfaces should not be given for module > procedures since they are provided implicitly. So how does one use > module procedures with argument keywords? Several confusions here. Much of it probably caused by incorrect terminology. An explicit interface for a procedure is basically the information about how to call the procedure (including, among other things, the argument names). The piece of code you show above is not an "explicit interface". It is an interface body in an interface block...(well sort of - it has several syntactic problems, but that's what you are trying to write). Writing an interface body in an interface block is one way of providing an explicit interface, but it is not the only way. Nor is it often a very good, or even possible, way. I'd guess that part of your confusion is that you are confusing these terms and thinking about interface bodies when you see the term "explicit interface". They are not synonyms. A module procedure *DOES* have an explicit interface - always. It comes with one by virtue of being a module procedure. And whenever you USE the module, that goves you access to the explicit interface information. That's basically why you can't write an interface body for a module procedure. The module procedure already has an explicit interface. If you try to give it one with an interface body, you'd be either duplicating or contradicting the one it already has. I'd really avoid the term "implicit" in this regard. Its perhaps correct, both gramatically and technically, to say that a module procedure implicitly has an explicit interface - which is to say that it does not have an implicit interface. But its darned confusing. The terminology is perhaps unfortunate (and is compounded by the distinction between an interface block and an interface body, but thankfully that part isn't directly at issue here). Now. Given any procedure with an accessible explicit interface, regardless of whether the interface was given by an interface body or was automatic by virtue of being a module procedure, what are the keywords? The keywords *ARE* the dummy argument names. You don't specify the keywords separately in the procedure or in the interface body. You just write the dummy arguments normally. By virtue of being dummy argument names in an explicit interface, they are available as keywords when you invoke the procedure. So for a module procedure, you don't have to do anything special to make the keywords available. Just USE the module (if you don't do that, then you can't call the procedure at all). Then you are free to use the keyword form in calls to it. The dummy argument names are the keywords. -- Richard Maine [log in to unmask] %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%