Questions tagged [setf]
The setf tag has no usage guidance.
9 questions
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Setf not expanding
I'm trying to modify a member of lsp--client after registration. So I have something like the following in use-package.
(message "%s %s" (symbol-function 'lsp--client-new-connection)
(...
- 211
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Getting error in hook: Symbol’s function definition is void: \(setf\ ekg-note-tags\)
I'm writing a pre-save hook for ekg (emacs knowledge graph), and getting an error I don't know how to figure out.
The error is triples--with-transaction: Symbol’s function definition is void: \(setf\ ...
- 496
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1
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How to find if an Emacs lisp function is setf-able?
Emacs Lisp setf macro allows you to set generalized variables. You can, for example change the size of the current window with the following form:
(setf (window-height) 10)
The macro will translate ...
- 841
3
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2
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960
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setf + alist-get but with "equal" instead of "eq"?
I got a suggestion to use setf to replace value in an alist: Replace element in a list / add in case of absence, with custom test/key functions
The example was provided, but it doesn't work if key is ...
- 3,552
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48
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`cl-incf` returns inconsistent values
(setq ali '())
>>> nil
(cl-incf (alist-get 'a ali 0))
>>> ((a . 1))
(setf (alist-get 'b ali) 0)
>>> ((b . 0) (a . 1))
(cl-incf (alist-get 'b ali 0))
>>> 1
As you ...
- 185
4
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1
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421
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How can I make `setf` work with `plist-get`?
There's no built-in setter for plist-get. Example:
(let ((pl '(:what (one))))
(push 'two (plist-get pl :what))
pl)
Error: let*: Symbol’s function definition is void: \(setf\ plist-get\)
How can I ...
- 398
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Is there a generalized setter for buffer-modified-p?
It is very simple to define a simple generalized setter for buffer-modified-p:
(gv-define-simple-setter buffer-modified-p set-buffer-modified-p)
That enables constructs like:
(with-current-buffer "...
- 33.7k
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3
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How do I remove :width and :height from an image created with create-image?
I am trying to make jabber.el support images sent from e.g. Conversations.
I download the image using url-retrieve-synchonously and call create-image to get an image which I can then use with insert-...
- 1,087
7
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1
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472
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Setf weird expansion
Trying to understand what setf can do, I called
(macroexpand '(setf (aref vec i) val))
⇒ (let* ((v vec) (v i)) (aset v v val))
This seems obviously wrong.
However I couldn't create an actual ...
- 1,249