Clipper is a programming language that was developed in the mid-1980s by Nantucket Corporation, as a powerful extension of the dBASE III language. It was widely used in business and scientific applications, particularly in the development of database management systems. The language was known for its speed and efficiency, and its ability to handle large amounts of data with ease. In this beginner's guide, we will explore the basics of Clipper programming, learn how to write simple programs with an example, and discuss the best applications for the language.
Introduction to Clipper
Clipper is a compiled xBase language, meaning that it is first converted into machine code before execution, which makes it very fast and efficient. It was initially designed to work with dBASE III, but later versions of Clipper were developed to be used as standalone programming languages. Clipper programs are stored in plain text files with a .prg extension, and they can be executed from the command line or from within an Integrated Development Environment (IDE).
Getting Started with Clipper
To get started with Clipper, you will need a text editor and a compiler. There are several compilers available, but one of the most popular is Harbour, an open-source compiler that is compatible with Clipper syntax. You can download the Harbour compiler from its website and install it on your computer.
Once you have installed the compiler, you can create a new text file with a .prg extension and start writing your Clipper program. The syntax of Clipper is very similar to dBASE III, but with some added features that make it more powerful. For example, Clipper supports object-oriented programming, which allows you to define classes and objects, and it has a more robust set of control structures and functions.
Writing a Simple Clipper Program
Let's create a simple Clipper program that prompts the user for their name and then greets them. Here's the code:
```
PROCEDURE Main
? "What is your name?"
cName := Read()
? "Hello, " + cName + "!"
RETURN
```
This program defines a procedure called Main, which prompts the user for their name using the ? operator (which is equivalent to the PRINT statement in other languages), reads the user's input using the Read() function, and then prints a greeting using the concatenation operator (+).
To compile and run this program, save it as a .prg file, open a command prompt, navigate to the directory where the file is saved, and type the following command:
```
hbclip program.prg
```
This will compile the program and create an executable file with the same name as the program, but with a .exe extension. To run the program, simply type the name of the executable file at the command prompt.
Applications of Clipper
Clipper was widely used in the development of business and scientific applications, particularly in the area of database management systems. It was known for its speed and efficiency, which made it an ideal choice for applications that needed to process large amounts of data quickly. Some of the applications that were developed using Clipper include accounting software, inventory management systems, and medical record keeping systems.
Conclusion
Clipper is a powerful programming language that was widely used in the 1980s and 1990s for business and scientific applications. It is a compiled xBase language that is very fast and efficient, and it supports object-oriented programming and a robust set of control structures and functions. In this beginner's guide, we learned how to write a simple Clipper program, and we discussed some of the best applications for the language. If you are interested in learning more about Clipper, there are several resources available online, including tutorials and forums where you can ask questions and get help from other programmers.
Clipper may no longer be as widely used as it once was, but it remains an important part of the history of programming languages. Its influence can be seen in many modern programming languages, particularly in the area of database management systems. If you are interested in learning more about programming languages and their history, Clipper is a great place to start.