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0 pointsmasklinn1y ago0 comments

> Emacs Lisp retains dynamic scope, but it's no longer a default for some time now

https://www.gnu.org/software/emacs/manual/html_node/elisp/Va...

> By default, the local bindings that Emacs creates are dynamic bindings. Such a binding has dynamic scope, meaning that any part of the program can potentially access the variable binding. It also has dynamic extent, meaning that the binding lasts only while the binding construct (such as the body of a let form) is being executed.

It’s also not really germane to the GP’s comment, as they’re just talking about dynamic scoping being available, which it will almost certainly always be (because it’s useful).

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TeMPOraL1y ago

Sorry, you're right. It's not a cultural default anymore. I.e. Emacs Lisp got proper lexical scope some time ago, and since then, you're supposed to start every new .elisp file with:

  ;; -*- mode: emacs-lisp; lexical-binding: t; -*-

i.e. explicitly switching the interpreter/compiler to work in lexical binding mode.

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