Hi,

if I consult the definition of |isearch-filter-predicate|, I find:

    Predicate to filter hits of Isearch and replace commands. Isearch hits
    that don’t satisfy the predicate will be skipped.

Over the years, I have found this option very useful as it allows me to 
perform targeted searches and replacements in certain parts of the 
|LaTeX| documents I edit for work.
For example, by creating custom predicates, I can ensure that I operate 
only on the mathematical part of the document, or only on 
cross-reference labels; I can ignore comments inserted by the authors, 
and so on.

Unfortunately, however, some functions such as |occur|, 
|search-forward-*|, |string-match*|, do not take this variable into account.

For some of them, I managed to create modified versions:

|(defun search-forward-ifp (STRING &optional BOUND NOERROR COUNT) 
"Modified version of `search-forward` that filters (skips) matches 
according to `isearch-filter-predicate'." (let ((POINT (point))) (catch 
'filtered (while (search-forward STRING BOUND NOERROR COUNT) (let ((B 
(match-beginning 0)) (E (match-end 0))) ;; 1 - If all points of the 
region matching the search from ;; the previous `search-forward` fit the 
criteria accepted ;; by the filter, then the loop stops (throw) and ;; 
returns the position `(point)`: (when (funcall isearch-filter-predicate 
B E) (throw 'filtered (point))))) ;; 2 - If the search is unsuccessful, 
or it doesn't fit ;; the criteria accepted by the filter, then return to 
;; the starting position and return `nil`. (goto-char POINT) nil))) |

However, I couldn’t modify, for instance, |occur| and 
|string-match(-p)|. Is there a reason why these functions don’t adopt 
this mechanism? Or is it simply a lack of interest in implementing this 
option?

(I understand that the “i” in [i]search stands for interactive, but I 
often find myself using functions that are not strictly interactive 
within functions that are.)

It make sense to open a feature request?

Best regards,

Gabriele Nicolardi

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