Re: [BLACKBOX] Delphi-like parameters in Array Of Const

From: [at]} <Romiras>
Date: Mon, 11 Oct 2010 12:54:18 +0200

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> A (type safe) way to do this in CP is to have one parameter which is a
> linked list of objects, each of which can be a different type. We use this
> technique extensively (in Delphi, CP and GPCP software) to provide a generic
> way of maintaining INI file / Windows registry values. It supports the use
> of string, boolean and integer data types.
>
> If you are only dealing with a few values then it is a simple problem
> deserving a simple solution. Call a separate procedure for each value you
> wish to format. If you have groups of similar calls then collect these into
> one procedure with a fixed number of parameters. It might require a little
> more typing but is likely to be more secure / reliable and be easier to
> comprehend and maintain in the long term.
Well. It's seems like a reasonable solution for me.

Here is a prototype of my Format procedure:

PROCEDURE Format* (template: ARRAY OF CHAR; args: VarList; VAR res:
ARRAY OF CHAR);
        VAR node: VarList; var: BaseType;
BEGIN
        res := template$; node := args;
        WHILE node # NIL DO
                var := node^.var;
                WITH
                        var: BoolType DO InterpretAsBool(var, res) |
                        var: IntType DO InterpretAsInt(var, res) |
                        var: RealType DO InterpretAsReal(var, res) |
                        var: CharType DO InterpretAsChar(var, res) |
                        (*var: SomeType DO InterpretAs(var, res)*)
                END;
                node := node^.next
        END;
END Format;

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Received on Mon Oct 11 2010 - 12:54:18 UTC