diff options
Diffstat (limited to 'lisp/emacs-lisp/text-property-search.el')
| -rw-r--r-- | lisp/emacs-lisp/text-property-search.el | 62 |
1 files changed, 42 insertions, 20 deletions
diff --git a/lisp/emacs-lisp/text-property-search.el b/lisp/emacs-lisp/text-property-search.el index 6b315a11066..7da02a9cb2d 100644 --- a/lisp/emacs-lisp/text-property-search.el +++ b/lisp/emacs-lisp/text-property-search.el @@ -31,28 +31,40 @@ (defun text-property-search-forward (property &optional value predicate not-current) - "Search for the next region of text whose PROPERTY matches VALUE. - -If not found, return nil and don't move point. -If found, move point to end of the region and return a `prop-match' -object describing the match. To access the details of the match, -use `prop-match-beginning' and `prop-match-end' for the buffer -positions that limit the region, and `prop-match-value' for the -value of PROPERTY in the region. - + "Search for the next region of text where PREDICATE is true. PREDICATE is used to decide whether a value of PROPERTY should be considered as matching VALUE. -If PREDICATE is t, that means a value must `equal' VALUE to be -considered a match. -If PREDICATE is nil, a value will match if it is non-nil and -is NOT `equal' to VALUE. + If PREDICATE is a function, it will be called with two arguments: VALUE and the value of PROPERTY. The function should return non-nil if these two values are to be considered a match. +Two special values of PREDICATE can also be used: +If PREDICATE is t, that means a value must `equal' VALUE to be +considered a match. +If PREDICATE is nil (which is the default value), a value will +match if is not `equal' to VALUE. Furthermore, a nil PREDICATE +means that the match region is ended if the value changes. For +instance, this means that if you loop with + + (while (setq prop (text-property-search-forward 'face)) + ...) + +you will get all distinct regions with non-nil `face' values in +the buffer, and the `prop' object will have the details about the +match. See the manual for more details and examples about how +VALUE and PREDICATE interact. + If NOT-CURRENT is non-nil, the function will search for the first region that doesn't include point and has a value of PROPERTY -that matches VALUE." +that matches VALUE. + +If no matches can be found, return nil and don't move point. +If found, move point to the end of the region and return a +`prop-match' object describing the match. To access the details +of the match, use `prop-match-beginning' and `prop-match-end' for +the buffer positions that limit the region, and +`prop-match-value' for the value of PROPERTY in the region." (interactive (list (let ((string (completing-read "Search for property: " obarray))) @@ -125,7 +137,7 @@ that matches VALUE." "Search for the previous region of text whose PROPERTY matches VALUE. Like `text-property-search-forward', which see, but searches backward, -and if a matching region is found, moves point to its beginning." +and if a matching region is found, place point at the start of the region." (interactive (list (let ((string (completing-read "Search for property: " obarray))) @@ -137,11 +149,19 @@ and if a matching region is found, moves point to its beginning." nil) ;; We're standing in the property we're looking for, so find the ;; end. - ((and (text-property--match-p - value (get-text-property (1- (point)) property) - predicate) - (not not-current)) - (text-property--find-end-backward (1- (point)) property value predicate)) + ((text-property--match-p + value (get-text-property (1- (point)) property) + predicate) + (let ((origin (point)) + (match (text-property--find-end-backward + (1- (point)) property value predicate))) + ;; When we want to ignore the current element, then repeat the + ;; search if we haven't moved out of it yet. + (if (and not-current + (equal (get-text-property (point) property) + (get-text-property origin property))) + (text-property-search-backward property value predicate) + match))) (t (let ((origin (point)) (ended nil) @@ -206,3 +226,5 @@ and if a matching region is found, moves point to its beginning." (funcall predicate value prop-value)) (provide 'text-property-search) + +;;; text-property-search.el ends here |