[O] Circular lists/shared structures in org-element parse-tree
Hi List, I wonder how I can find out in a (elisp) program the points in the parse tree (returned by org-element-parse-buffer) where shared structures are used. In the read-syntax, its easy to see (especially with `print-circle' set to non-nil): #+begin_src emacs-lisp #2=(org-data nil #1=(headline (:raw-value header 1 [...] :parent #2#) [...] #+end_src but when processing the parse tree as a list in elisp, how can I detect the fact that , | :parent #2# ` refers to ,- | #2=(org-data nil `- i.e. points back to an already existing structure? -- cheers, Thorsten
Re: [O] Circular lists/shared structures in org-element parse-tree
Thorsten Jolitz tjol...@gmail.com writes: Hi List, I wonder how I can find out in a (elisp) program the points in the parse tree (returned by org-element-parse-buffer) where shared structures are used. In the read-syntax, its easy to see (especially with `print-circle' set to non-nil): #+begin_src emacs-lisp #2=(org-data nil #1=(headline (:raw-value header 1 [...] :parent #2#) [...] #+end_src but when processing the parse tree as a list in elisp, how can I detect the fact that , | :parent #2# ` refers to ,- | #2=(org-data nil `- i.e. points back to an already existing structure? AFAIK you have to track all pointers inspected to see if one has already be seen. For example, I've implemented a version of equal[1] to compare this kind of lists (to add tests to org-sync). [1] https://github.com/daimrod/Emacs-config/blob/master/elisp/dmd-utils.el#L25 -- Daimrod/Greg signature.asc Description: PGP signature
Re: [O] Circular lists/shared structures in org-element parse-tree
Daimrod daim...@gmail.com writes: Thorsten Jolitz tjol...@gmail.com writes: [...] but when processing the parse tree as a list in elisp, how can I detect the fact that , | :parent #2# ` refers to ,- | #2=(org-data nil `- i.e. points back to an already existing structure? AFAIK you have to track all pointers inspected to see if one has already be seen. For example, I've implemented a version of equal[1] to compare this kind of lists (to add tests to org-sync). [1] https://github.com/daimrod/Emacs-config/blob/master/elisp/dmd-utils.el#L25 Oh my ... I knew this would complicate my life a bit ... Thanks for the link, this example function is indeed very helpful. -- cheers, Thorsten
