Introduction to Ada 2012

Subprograms
Welcome to the module on subprograms. I'm Tod Gentille from Pluralsight. In this module, we'll be discussing Scope, Functions, and Procedures. The distinction in Ada is that functions return a value and procedures do not. In either case, the body of the subprogram executes, just like the code we've been seeing. Of course, you can pass in parameters, and in Ada you can even specify the mode of those parameters, that is you can specify whether a parameter is an input, an output, or an input output. Just like aggregates, subprogram parameters can be specified by position or name. Parameters also support default values. From the sneak peek we got at generic programming in Ada, you've probably guessed that Ada subprograms also support overloading. That is, if the number, order, and type of parameters isn't the same, then the subprograms can all have the same name and Ada will know which one to call. Furthermore, functions can't hide procedures, so you could have a function and a procedure with identical names that take no parameters and Ada will properly disambiguate them. We'll get to all this and more in this module, but in the next clip let's delve into scope and talk about nested blocks in Ada.