2.1 The Prolog+CG screen

Main screen

Once the Prolog+CG environment has been started, you will see a screen that looks like this:

There are two main sections of the Prolog+CG window. In the upper section (the program area), you write and edit your programs, while in the lower section (the query area), you write questions to ask the Prolog system. The splitter between the two sections can be dragged to make either section bigger or smaller.


The toolbar provides easy access to the most common commands. This button:

is the compile-button. Use it every time you have modified the program text. (The term 'compile' will be explained on the next page.)

This button:

is the query-button. You can use it to start the Prolog engine on the question you have written in the query-area.

This button:

is the stop-button. You can use it to stop the Prolog engine as it searches for solutions to your question, if it takes too long.


The Prolog+CG window is divided into main two areas:

  • The program area
  • The query area

The toolbar provides easy access to the most commonly used functions, such as:

  • The compile button
  • The query button
  • The stop button


The next section explains the development cycle of Prolog.

PrevLite: 2 The Prolog+CG environment
NextLite: 2.2 The Prolog development cycle

Prev: 2 The Prolog+CG environment
Up: 2 The Prolog+CG environment
Next: 2.2 The Prolog development cycle