Notes on using Prolog on the lab Macs:

Instructions from the CS lab machines -- or from a Mac once Prolog is installed:

You'll want to log in and download the HW files. We'll suppose that you download them to the Desktop.
Next, open a terminal window. You can use the Searchlight feature (upper right) to look for terminal. You'll see a command-line interface open up.
Next, change directory to the Desktop. This will use cd as follows: % cd Desktop You should see hw3pr1.pl when you type ls, which is the command to list all the files in the directory.
Next, you can open prolog with the command /usr/local/bin/swipl
Then, you can load a file, e.g., the hw3pr1.pl file at the prolog prompt with [hw3pr1]. - the period at the end is important!
You may see warnings about "Singleton variables" - don't worry about these for now.
You can also load a file upon starting with /usr/local/bin/swipl -f hw3pr1.pl or any other file name you'd like. Remember that you can use the up arrow to repeat a command you've typed earlier (so that there's no need to retype it).
You might try predicates such as parent(X, bart). once the hw3pr1.pl file is loaded. Recall that the semicolon means OR, and asks for more possible solutions. Hitting return stops the search for possible solutions to a predicate query.
To edit the hw3pr1.pl file, you might use any text editor at all. I use the Max OS built-in editor, named TextEdit, which can be found in Applications.
You will notice that the hw3pr1.pl file, as written, will cause Prolog to warn you about "singleton" variables. These warnings will (or, at least should) disappear when you write the predicates that are described in this week's hw.