help-gnu-emacs
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: How to test if symbol from string exists?


From: Jean Louis
Subject: Re: How to test if symbol from string exists?
Date: Fri, 16 Apr 2021 13:04:45 +0300
User-agent: Mutt/2.0.6 (2021-03-06)

* Philip Kaludercic <philipk@posteo.net> [2021-04-16 12:23]:
> Jean Louis <bugs@gnu.support> writes:
> 
> > I would like to test if symbol exists and is true.
> >
> > First I have string, like "people", then I can do this:
> >
> > (symbol-value (intern "rcd-db-people-mode-map")) and it gives me
> > result.
> 
> I think you want to use intern-soft, to return a symbol if it exists,
> and nil if it doesn't. If you want to check if it is "used", boundp
> should suffice, regardless of whether you use intern or intern-soft.

Thanks, I made it this way here:

(defun rcd-db-table-mode-map (table)
  (let ((symbol (format "rcd-db-%s-mode-map" table)))
  (if (intern-soft symbol)
      (symbol-value (intern symbol))
    rcd-db-mode-map)))

as that replaces now the function below and I can just add new
function with new string to invoke either the default or specialy
defined mode map.

;; (defun rcd-db-table-mode-map (table)
;;   (cond ((string= "accounts" table) rcd-db-accounts-mode-map)
;;      ((string= "acks" table) rcd-db-acks-mode-map)
;;      ((string= "addressbookentries" table) 
rcd-db-addressbookentries-mode-map)
;;      ((string= "areas" table) rcd-db-areas-mode-map)
;;      ((string= "categories" table) rcd-db-categories-mode-map)
;;      ((string= "countries" table) rcd-db-countries-mode-map)
;;      ((string= "devt" table) rcd-db-devt-mode-map)
;;      ((string= "edit" table) rcd-db-edit-mode-map)
;;      ((string= "emails" table) rcd-db-emails-mode-map)
;;      ((string= "groups" table) rcd-db-groups-mode-map)
;;      ((string= "locationsets" table) rcd-db-locationsets-mode-map)
;;      ((string= "mailinglistoptions" table) 
rcd-db-mailinglistoptions-mode-map)
;;      ((string= "notes" table) rcd-db-notes-mode-map)
;;      ((string= "pages" table) rcd-db-pages-mode-map)
;;      ((string= "people" table) rcd-db-people-mode-map)
;;      ((string= "skills" table) rcd-db-skills-mode-map)
;;      ((string= "sms" table) rcd-db-sms-mode-map)
;;      ((string= "statsdefinitions" table) rcd-db-statsdefinitions-mode-map)
;;      (t rcd-db-mode-map)))

-- 
Jean

Take action in Free Software Foundation campaigns:
https://www.fsf.org/campaigns

Sign an open letter in support of Richard M. Stallman
https://stallmansupport.org/
https://rms-support-letter.github.io/




reply via email to

[Prev in Thread] Current Thread [Next in Thread]