Command Line

Once SPA has been successfully started, the user issues commands which manipulate data or modify the state of the S file. The command line is case insensitive and is comprised of four elements:

1. arguments identifying the data on which one or more functions will operate,
2. punctuation to delimit and modify parts of a command,
3. functions specifying the operations to be performed upon the arguments,
4. result to specify the location to store the processed data.

Only the first three letters of a function name are significant. With the exception of those functions which modify the program, most operations require one or more arguments. Storing the result of an operation is optional although the last argument from a command line is stored by the program in a location labeled the X register.

• Arguments
• Results
• Functions
• Punctuation