Keyword Options

The optional string argument specifies a list of keywords recognized by the next user-input function call.

The initget function allows keyword abbreviations to be recognized in addition to the full keywords. The user-input function returns a predefined keyword if the input from the user matches the spelling of a keyword (not case sensitive), or if the user enters the abbreviation of a keyword. There are two methods for abbreviating keywords; both are discussed in the initget topic in the AutoLISP Reference.

The following user-defined function shows a call to getreal, preceded by a call to initget, that specifies two keywords. The application checks for these keywords and sets the input value accordingly.

(defun C:GETNUM (/ num)
  (initget 1 "Pi Two-pi") 
  (setq num (getreal "Pi/Two-pi/<number>: ")) 
	((eq num "Pi") pi) 
	((eq num "Two-pi") (* 2.0 pi)) 
	(T num) 

This initget call inhibits null input (bits =1) and establishes a list of two keywords, "Pi" and "Two-pi". The getreal function is then used to obtain a real number, issuing the following prompt:


The result is placed in local symbol num. If the user enters a number, that number is returned by C:GETNUM. However, if the user enters the keyword Pi (or simply P), getreal returns the keyword Pi. The cond function detects this and returns the value of p in this case. The Two-pi keyword is handled similarly.

NoteYou can also use initget to enable entsel, nentsel, and nentselp to accept keyword input. For more information on these functions, see Object Handling and the entsel, nentsel and nentselp function definitions in the AutoLISP Reference.