Positioning within operand forms

When an operand form is first displayed, the cursor is positioned to the beginning of the first input line. Positioning to a different line is achieved by moving the cursor as follows:

	The cursor moves to the same position in the following input line. Starting from the NEXT line, the cursor returns to the first input line.
	The cursor moves to the same position in the preceding input line. Starting from the first input line, the cursor moves to the beginning of the line. Starting from the NEXT line, the cursor moves to the beginning of the NEXT line.
	The cursor moves to the beginning of the following input line, skipping any continuation lines of the current line. Starting from the NEXT line, the cursor returns to the first input line.
	Starting from the beginning of an input line, the cursor moves to the beginning of the preceding input line. Starting from any other position, it moves to the beginning of the current input line.
	The cursor moves to the beginning of the first input line.
	The cursor moves to the beginning of an input line or continuation line. Starting from the first input line, it moves to the beginning of that line. Starting from the NEXT line, it moves to the beginning of the NEXT line.
	The cursor moves to the beginning of the following input line or continuation line. Starting from the NEXT line, it returns to the first input line.