Syntactical structure (1)
General: The CL should be designed such that users enter Cs in a manner which is natural or famliar to the user without concern for how the system will process the Cs to produce the output (e.g. the CL should reflect the user’s needs rather than the system process and the syntax structure should be be consistent with user expectations, task requirements and input devices).
Internal consistency: The CL should be internally consistent so Cs with the same name, function in the same way throughout the application regardless of the context. Cs that do the same thing should have the same name.
Macros: If sequences of command words or command phrases are used frequently, users should be allowed to create and use higher level commands (macros) for these sequences. [NOTE macros should follow the same recommendations as commands]
Argument structure: Command phrases should be be structured to minimize the complexity of arguments. Long Lists - if arguments are long (more than 8 arguments), then additional command names should be created, functions should be combined under single arguments, or lists should be broken into some logical functional groupings Dependencies - dependencies between arguments of a command should be not dramatically change the meaning of the command phrase (e.g. command “quit filename” to save data to the file named filename; command cancel to cancel without saving {instead of the more complex “quit -c”}