Ada Programming/Function overloading
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function Generate_Number (MaxValue : Integer) return Integer is subtype Random_Type is Integer range 0 .. MaxValue; package Random_Pack is new Ada.Numerics.Discrete_Random (Random_Type); G : Random_Pack.Generator; begin Random_Pack.Reset (G); return Random_Pack.Random (G); end Generate_Number; function Generate_Number (MinValue : Integer; MaxValue : Integer) return Integer is subtype Random_Type is Integer range MinValue .. MaxValue; package Random_Pack is new Ada.Numerics.Discrete_Random (Random_Type); G : Random_Pack.Generator; begin Random_Pack.Reset (G); return Random_Pack.Random (G); end Generate_Number;
Number_1 : Integer := Generate_Number (10);
Number_2 : Integer := Generate_Number (6, 10);
Function overloading in Ada [edit]
Ada supports all six signature options but if you use the arguments' name as option you will always have to name the parameter when calling the function. i.e.:
Number_2 : Integer := Generate_Number (MinValue => 6,
MaxValue => 10);
Note that you cannot overload a generic procedure or generic function within the same package. The following example will fail to compile:
package myPackage generic type Value_Type is (<>); -- The first declaration of a generic subprogram -- with the name "Generic_Subprogram" procedure Generic_Subprogram (Value : in out Value_Type); ... generic type Value_Type is (<>); -- This subprogram has the same name, but no -- input or output parameters. A non-generic -- procedure would be overloaded here. -- Since this procedure is generic, overloading -- is not allowed and this package will not compile. procedure Generic_Subprogram; ... generic type Value_Type is (<>); -- The same situation. -- Even though this is a function and not -- a procedure, generic overloading of -- the name "Generic_Subprogram" is not allowed. function Generic_Subprogram (Value : Value_Type) return Value_Type; end myPackage;
