Update of /project/gsharp/cvsroot/gsharp/Flexichain In directory common-lisp.net:/tmp/cvs-serv31819 Modified Files: flexichain-package.lisp flexirank.lisp Log Message: added flexi-first-p and flexi-last-p to flexirank.lisp Date: Mon Nov 28 22:27:03 2005 Author: rstrandh Index: gsharp/Flexichain/flexichain-package.lisp diff -u gsharp/Flexichain/flexichain-package.lisp:1.5 gsharp/Flexichain/flexichain-package.lisp:1.6 --- gsharp/Flexichain/flexichain-package.lisp:1.5 Mon Nov 28 00:43:50 2005 +++ gsharp/Flexichain/flexichain-package.lisp Mon Nov 28 22:27:02 2005 @@ -38,5 +38,6 @@ #:insert #:insert-sequence #:element< #:element> #:delete< #:delete> #:flexirank-mixin #:element-rank-mixin #:rank + #:flexi-first-p #:flexi-last-p #:flexi-next #:flexi-prev)) Index: gsharp/Flexichain/flexirank.lisp diff -u gsharp/Flexichain/flexirank.lisp:1.3 gsharp/Flexichain/flexirank.lisp:1.4 --- gsharp/Flexichain/flexirank.lisp:1.3 Mon Nov 28 01:25:59 2005 +++ gsharp/Flexichain/flexirank.lisp Mon Nov 28 22:27:02 2005 @@ -28,6 +28,8 @@ ;;; generic function rank. (defgeneric rank (element)) +(defgeneric flexi-first-p (element)) +(defgeneric flexi-last-p (element)) (defgeneric flexi-next (element)) (defgeneric flexi-prev (element)) @@ -38,16 +40,19 @@ (defmethod rank ((element element-rank-mixin)) (index-position (chain element) (index element))) +(defmethod flexi-first-p ((element element-rank-mixin)) + (zerop (rank element))) + +(defmethod flexi-last-p ((element element-rank-mixin)) + (= (rank element) (1- (nb-elements (chain element))))) + (defmethod flexi-next ((element element-rank-mixin)) - (let ((new-rank (1+ (rank element))) - (chain (chain element))) - (assert (< new-rank (nb-elements chain))) - (element* chain new-rank))) + (assert (not (flexi-last-p element))) + (element* (chain element) (1+ (rank element)))) (defmethod flexi-prev ((element element-rank-mixin)) - (let ((new-rank (1- (rank element)))) - (assert (not (minusp new-rank))) - (element* (chain element) new-rank))) + (assert (not (flexi-first-p element))) + (element* (chain element) (1- (rank element)))) ;;; this class must be mixed into a flexichain that contains ranked elements (defclass flexirank-mixin () ())