Commands Used to Create and Edit Expressions

The Backspace, Enter, Delete, and Insert keystrokes are all tied to commands so that the action of these keystrokes on expressions can be modified and extended as new libraries are created.

Commands used to create and edit expressions include:

  • The Backspace command is designed to behave as much like an ordinary backspace on a line of text as is possible.
  • The Enter command works on some objects to insert a new parameter or to start a list. For example, if the highlight is on the left-hand side of an Assert, the Enter key will create an And object. On the right-hand side of an Assert, the Enter key will create an ElseList.
  • The Insert command typically adds another parameter to an expression.
  • The Delete command typically replaces the highlighted expression with an empty box.

The Building Expressions section describes other commands (like "+", "-", etc.) that are used to construct new expressions.