Hi Eli, may be. But in my case it didn't. I was misled by the term 'local variable' coming from (and using) other programming languages. As I understood the text (and to continue with the system-time-locale) I understood as local variable a 'value that was stored in the function's stack' to be used in the scope of the let. That implied (once again in my understanding) that the global system-time-locale would not be affected and hence format-time-string would not see the change in the value within the let. An example like this would have helped me (and possibly shaped the way I use elisp)... Just my .02 cents, /PA On Tue, 4 Oct 2022 at 09:52, Eli Zaretskii wrote: > > From: Pedro Andres Aranda Gutierrez > > Date: Tue, 4 Oct 2022 08:46:02 +0200 > > > > this is a small patch for the 'Introduction to Emacs LISP programming' > guide to show how let works on > > system-wide variables. > > Understanding this would have made my life easier the past +20 years ;-) > and an example is sometimes > > worth 100 lines of explanation (more so if you are in a hurry and you do > diagonal reading) > > This manual already says, in the previous subsection: > > Local variables created by a ‘let’ expression retain their value > _only_ within the ‘let’ expression itself (and within expressions called > within the ‘let’ expression); the local variables have no effect outside > the ‘let’ expression. > > Doesn't this cover the issue? > -- Fragen sind nicht da um beantwortet zu werden, Fragen sind da um gestellt zu werden Georg Kreisler Headaches with a Juju log: unit-basic-16: 09:17:36 WARNING juju.worker.uniter.operation we should run a leader-deposed hook here, but we can't yet