A-M baby

Task/Higher-order-functions/Ada/higher-order-functions-1.ada

@@ -0,0 +1,17 @@
+with Ada.Text_Io; use Ada.Text_Io;
+
+procedure Subprogram_As_Argument is
+   type Proc_Access is access procedure;
+
+   procedure Second is
+   begin
+      Put_Line("Second Procedure");
+   end Second;
+
+   procedure First(Proc : Proc_Access) is
+   begin
+      Proc.all;
+   end First;
+begin
+   First(Second'Access);
+end Subprogram_As_Argument;

Task/Higher-order-functions/Ada/higher-order-functions-2.ada

@@ -0,0 +1,52 @@
+with Ada.Text_Io; use Ada.Text_Io;
+
+procedure Subprogram_As_Argument_2 is
+
+   -- Definition of an access to long_float
+
+   type Lf_Access is access Long_Float;
+
+   -- Definition of a function returning Lf_Access taking an
+   -- integer as a parameter
+
+   function Func_To_Be_Passed(Item : Integer) return Lf_Access is
+      Result : Lf_Access := new Long_Float;
+   begin
+      Result.All := 3.14159 * Long_Float(Item);
+      return Result;
+   end Func_To_Be_Passed;
+
+   -- Definition of an access to function type matching the function
+   -- signature above
+
+   type Func_Access is access function(Item : Integer) return Lf_Access;
+
+   -- Definition of an integer access type
+
+   type Int_Access is access Integer;
+
+   -- Define a function taking an instance of Func_Access as its
+   -- parameter and returning an integer access type
+
+   function Complex_Func(Item : Func_Access; Parm2 : Integer) return Int_Access is
+      Result : Int_Access := new Integer;
+   begin
+      Result.All := Integer(Item(Parm2).all / 3.14149);
+      return Result;
+   end Complex_Func;
+
+   -- Declare an access variable to hold the access to the function
+
+   F_Ptr : Func_Access := Func_To_Be_Passed'access;
+
+   -- Declare an access to integer variable to hold the result
+
+   Int_Ptr : Int_Access;
+
+begin
+
+   -- Call the function using the access variable
+
+   Int_Ptr := Complex_Func(F_Ptr, 3);
+   Put_Line(Integer'Image(Int_Ptr.All));
+end Subprogram_As_Argument_2;