When I open a Clojure file, and I'm not using Paredit, I expect to be able to type unbalanced parentheses and brackets. I can type any of these characters: ()[]{, balanced on not. But if I try to type a } that has no matching start {, it won't let me.
Why is this? And how do I turn it off? I expect this type of behavior in paredit-mode, but outside of that mode I want to be free to type any characters.
GNU Emacs 25.3.1 on macOS. Clojure mode 5.8.2.
The problem only occurs after you've turned paredit on and off: this is because clojure-mode adds a hook to paredit-mode, and that hook adds some paredit-mode keybindings to the clojure-mode map.
In other words, turning on paredit-mode makes changes to clojure-mode keybindings and those changes stick even if you turn off paredit-mode. The really surprising thing is if you edit a file in clojure-mode, then use paredit-mode in a different file, returning to the clojure file you'll get the paredit keybindings for "{" and "}".
That's arguably a bug in clojure-mode.
This has been reported as a bug (not by me), although I'm not sure if the maintainer agrees: https://github.com/clojure-emacs/clojure-mode/issues/504
You can insert unbalanced parentheses with C-q (quoted-insert).
If you really don't want Clojure Mode to bind { and } to ParEdit keys, here is a work-around:
(add-hook 'clojure-mode-hook (lambda () (remove-hook 'paredit-mode-hook #'clojure-paredit-setup))) (You need to restart Emacs, since once clojure-paredit-setup runs, the keys is set)
emacs -Q(no init file)? If so, please provide a step-by-step recipe to reproduce it. If not, bisect your init file to find the culprit.}character.