Problems deriving a theme from something other than modus

[jdtsmith]

modus-themes v20251122.1448, ef-themes v2.0.1, standard-themes v3.0.2

I'm attempting to port an old theme I use (and have modified) into the modus-landscape using the new capabilities for deriving themes via modus-theme-themes.

I'm trying this simple derivation using:

(modus-themes-theme
 'modus-alect-dark
 'modus-alect-themes
 "A dark theme in the modus family similar to alect-dark."
 'dark
 'standard-dark-palette
 'modus-alect-palette
 nil)

but am getting various errors.

No ability to require standard-dark-theme

Because I want to inherit from standard-dark-palette, I need to load it:

(require 'standard-dark-theme)

This throws:

Debugger entered--Lisp error: (error "Loading file .../.emacs.d/elpa/standard-themes-3.0.2/standard-dark-theme.elc failed to provide feature ‘standard-dark-theme’")
  require(standard-dark-theme)

I try require-theme: it does the same.

How are you supposed to derive from a theme which is not loaded? Do you need to load it first? All the examples in the manual show deriving from an already-loaded modus-theme (like modus-operandi). Maybe:

(load-theme 'standard-dark t t)

is the right approach? Would be good to have in the manual if so.

Bare symbol errors deriving themes

With that out of the way, other errors are encountered on evaluating the modus-themes-theme stanza above. modus appears to be unhappy with some "bare" symbols, e.g. bg-completion-match-0:

void-variable backtrace

Debugger entered--Lisp error: (void-variable bg-completion-match-0)
  (modus-themes--completion-match fg-completion-match-0 bg-completion-match-0)
  (cons c (modus-themes--completion-match fg-completion-match-0 bg-completion-match-0))
  (list (cons c (modus-themes--completion-match fg-completion-match-0 bg-completion-match-0)))
  (list 'modus-themes-completion-match-0 (list (cons c (modus-themes--completion-match fg-completion-match-0 bg-completion-match-0))))
  `(modus-themes-completion-match-0 ((,c ,@(modus-themes--completion-match fg-completion-match-0 bg-completion-match-0))))
  (custom-theme-set-faces 'modus-alect-dark `(modus-themes-heading-0 ((,c ,@(modus-themes--heading 0 fg-heading-0 bg-heading-0 overline-heading-0)))) `(modus-themes-heading-1 ((,c ,@(modus-themes--heading 1 fg-heading-1 bg-heading-1 overline-heading-1)))) `(modus-themes-heading-2 ((,c ,@(modus-themes--heading 2 fg-heading-2 bg-heading-2 overline-heading-2)))) `(modus-themes-heading-3 ((,c ,@(modus-themes--heading 3 fg-heading-3 bg-heading-3 overline-heading-3)))) `(modus-themes-heading-4 ((,c ,@(modus-themes--heading 4 fg-heading-4 bg-heading-4 overline-heading-4)))) `(modus-themes-heading-5 ((,c ,@(modus-themes--heading 5 fg-heading-5 bg-heading-5 overline-heading-5)))) `(modus-themes-heading-6 ((,c ,@(modus-themes--heading 6 fg-heading-6 bg-heading-6 overline-heading-6)))) `(modus-themes-heading-7 ((,c ,@(modus-themes--heading 7 fg-heading-7 bg-heading-7 overline-heading-7)))) `(modus-themes-heading-8 ((,c ,@(modus-themes--heading 8 fg-heading-8 bg-heading-8 overline-heading-8)))) `(modus-themes-completion-match-0 ((,c ,@(modus-themes--completion-match fg-completion-match-0 bg-completion-match-0)))) `(modus-themes-completion-match-1 ((,c ,@(modus-themes--completion-match fg-completion-match-1 bg-completion-match-1)))) `(modus-themes-completion-match-2 ((,c ,@(modus-themes--completion-match fg-completion-match-2 bg-completion-match-2)))) `(modus-themes-completion-match-3 ((,c ,@(modus-themes--completion-match fg-completion-match-3 bg-completion-match-3)))) `(modus-themes-completion-selected ((,c ,@(modus-themes--completion-line bg-completion)))) `(modus-themes-bold ((,c ,@(modus-themes--bold-weight)))) `(modus-themes-fixed-pitch ((,c ,@(modus-themes--fixed-pitch)))) `(modus-themes-slant ((,c ,@(modus-themes--slant)))) `(modus-themes-ui-variable-pitch ((,c ,@(modus-themes--variable-pitch-ui)))) `(modus-themes-button ((default :inherit variable-pitch :background ,bg-button-active :foreground ,fg-button-active) (((supports :box t)) :box (:line-width 1 :color ,border :style released-button)) (t :underline ,border))) `(modus-themes-prompt ((,c ,@(modus-themes--prompt fg-prompt bg-prompt)))) `(modus-themes-reset-soft ((,c :background ,bg-main :foreground ,fg-main :weight normal :slant normal :strike-through nil :box nil :underline nil :overline nil :extend nil))) `(default ((,c :background ,bg-main :foreground ,fg-main))) `(bold ((,c :weight bold))) `(bold-italic ((,c :inherit (bold italic)))) `(underline ((,c :underline ,fg-dim))) `(italic ((,c :slant italic))) `(cursor ((,c :background ,cursor))) `(fringe ((,c :background ,fringe :foreground ,fg-main))) `(menu ((,c :background ,bg-dim :foreground ,fg-main))) `(scroll-bar ((,c :background ,fringe :foreground ,border))) `(tool-bar ((,c :background ,bg-dim :foreground ,fg-main))) `(vertical-border ((,c :foreground ,border))) `(abbrev-table-name ((,c :inherit modus-themes-heading-1))) `(appt-notification ((,c :inherit modus-themes-bold :foreground ,modeline-err))) `(blink-matching-paren-offscreen ((,c :background ,bg-paren-match))) `(buffer-menu-buffer ((,c :foreground ,name))) `(child-frame-border ((,c :background ,border))) `(comint-highlight-input ((,c :inherit modus-themes-bold))) `(comint-highlight-prompt ((,c :inherit modus-themes-prompt))) `(confusingly-reordered ((,c :underline (:style wave :color ,underline-err)))) `(edmacro-label ((,c :inherit modus-themes-bold :foreground ,accent-0))) `(error ((,c :inherit modus-themes-bold :foreground ,err))) `(escape-glyph ((,c :inherit modus-themes-bold :foreground ,keybind))) `(file-name-shadow ((,c :foreground ,fg-dim))) `(header-line ((,c :inherit modus-themes-ui-variable-pitch :background ,bg-dim))) `(header-line-inactive ((,c :inherit modus-themes-ui-variable-pitch :background ,bg-dim :foreground ,fg-dim))) `(header-line-highlight ((,c :background ,bg-hover :foreground ,fg-main :box ,fg-main))) `(help-argument-name ((,c :inherit modus-themes-slant :foreground ,variable))) ...)
  (let* ((c '(... ...)) (palette (modus-themes--get-theme-palette-subr 'modus-alect-dark :with-overrides :with-user-palette)) (fringe (modus-themes--retrieve-palette-value 'fringe palette)) (border-mode-line-active (modus-themes--retrieve-palette-value 'border-mode-line-active palette)) (border-mode-line-inactive (modus-themes--retrieve-palette-value 'border-mode-line-inactive palette)) (blue (modus-themes--retrieve-palette-value 'blue palette)) (blue-faint (modus-themes--retrieve-palette-value 'blue-faint palette)) (green (modus-themes--retrieve-palette-value 'green palette)) (green-faint (modus-themes--retrieve-palette-value 'green-faint palette)) (red (modus-themes--retrieve-palette-value 'red palette)) (red-faint (modus-themes--retrieve-palette-value 'red-faint palette)) (yellow (modus-themes--retrieve-palette-value 'yellow palette)) (yellow-faint (modus-themes--retrieve-palette-value 'yellow-faint palette)) (magenta (modus-themes--retrieve-palette-value 'magenta palette)) (magenta-faint (modus-themes--retrieve-palette-value 'magenta-faint palette)) (cyan (modus-themes--retrieve-palette-value 'cyan palette)) (cyan-faint (modus-themes--retrieve-palette-value 'cyan-faint palette)) (rainbow-0 (modus-themes--retrieve-palette-value 'rainbow-0 palette)) (rainbow-1 (modus-themes--retrieve-palette-value 'rainbow-1 palette)) (rainbow-2 (modus-themes--retrieve-palette-value 'rainbow-2 palette)) (rainbow-3 (modus-themes--retrieve-palette-value 'rainbow-3 palette)) (rainbow-4 (modus-themes--retrieve-palette-value 'rainbow-4 palette)) (rainbow-5 (modus-themes--retrieve-palette-value 'rainbow-5 palette)) (rainbow-6 (modus-themes--retrieve-palette-value 'rainbow-6 palette)) (rainbow-7 (modus-themes--retrieve-palette-value 'rainbow-7 palette)) (rainbow-8 (modus-themes--retrieve-palette-value 'rainbow-8 palette)) (bg-main (modus-themes--retrieve-palette-value 'bg-main palette)) (fg-main (modus-themes--retrieve-palette-value 'fg-main palette)) (bg-dim (modus-themes--retrieve-palette-value 'bg-dim palette)) (fg-dim (modus-themes--retrieve-palette-value 'fg-dim palette)) (bg-alt (modus-themes--retrieve-palette-value 'bg-alt palette)) (fg-alt (modus-themes--retrieve-palette-value 'fg-alt palette)) ...) (custom-theme-set-faces 'modus-alect-dark `(modus-themes-heading-0 (...)) `(modus-themes-heading-1 (...)) `(modus-themes-heading-2 (...)) `(modus-themes-heading-3 (...)) `(modus-themes-heading-4 (...)) `(modus-themes-heading-5 (...)) `(modus-themes-heading-6 (...)) `(modus-themes-heading-7 (...)) `(modus-themes-heading-8 (...)) `(modus-themes-completion-match-0 (...)) `(modus-themes-completion-match-1 (...)) `(modus-themes-completion-match-2 (...)) `(modus-themes-completion-match-3 (...)) `(modus-themes-completion-selected (...)) `(modus-themes-bold (...)) `(modus-themes-fixed-pitch (...)) `(modus-themes-slant (...)) `(modus-themes-ui-variable-pitch (...)) `(modus-themes-button (... ... ...)) `(modus-themes-prompt (...)) `(modus-themes-reset-soft (...)) `(default (...)) `(bold (...)) `(bold-italic (...)) `(underline (...)) `(italic (...)) `(cursor (...)) `(fringe (...)) `(menu (...)) `(scroll-bar (...)) ...) (custom-theme-set-variables 'modus-alect-dark `(ansi-color-faces-vector [default bold shadow italic underline success warning error]) `(ansi-color-names-vector ["#595959" ... ... ... ... ... ... "#a6a6a6"]) `(chart-face-color-list '...) `(exwm-floating-border-color ,border) `(highlight-changes-colors nil) `(highlight-changes-face-list '...) `(ibuffer-filter-group-name-face 'bold) `(ibuffer-title-face 'default) `(hl-todo-keyword-faces '...) `(pdf-view-midnight-colors '...) `(rustic-ansi-faces [... ... ... ... ... ... ... ...]) `(viper-replace-overlay-cursor-color ,err) `(viper-insert-state-cursor-color ,info) `(viper-emacs-state-cursor-color ,fg-main) `(xterm-color-names [... ... ... ... ... ... ... ...]) `(xterm-color-names-bright [... ... ... ... ... ... ... ...]) '(frame-background-mode 'dark)))
  eval((let* ((c '(... ...)) (palette (modus-themes--get-theme-palette-subr 'modus-alect-dark :with-overrides :with-user-palette)) (fringe (modus-themes--retrieve-palette-value 'fringe palette)) (border-mode-line-active (modus-themes--retrieve-palette-value 'border-mode-line-active palette)) (border-mode-line-inactive (modus-themes--retrieve-palette-value 'border-mode-line-inactive palette)) (blue (modus-themes--retrieve-palette-value 'blue palette)) (blue-faint (modus-themes--retrieve-palette-value 'blue-faint palette)) (green (modus-themes--retrieve-palette-value 'green palette)) (green-faint (modus-themes--retrieve-palette-value 'green-faint palette)) (red (modus-themes--retrieve-palette-value 'red palette)) (red-faint (modus-themes--retrieve-palette-value 'red-faint palette)) (yellow (modus-themes--retrieve-palette-value 'yellow palette)) (yellow-faint (modus-themes--retrieve-palette-value 'yellow-faint palette)) (magenta (modus-themes--retrieve-palette-value 'magenta palette)) (magenta-faint (modus-themes--retrieve-palette-value 'magenta-faint palette)) (cyan (modus-themes--retrieve-palette-value 'cyan palette)) (cyan-faint (modus-themes--retrieve-palette-value 'cyan-faint palette)) (rainbow-0 (modus-themes--retrieve-palette-value 'rainbow-0 palette)) (rainbow-1 (modus-themes--retrieve-palette-value 'rainbow-1 palette)) (rainbow-2 (modus-themes--retrieve-palette-value 'rainbow-2 palette)) (rainbow-3 (modus-themes--retrieve-palette-value 'rainbow-3 palette)) (rainbow-4 (modus-themes--retrieve-palette-value 'rainbow-4 palette)) (rainbow-5 (modus-themes--retrieve-palette-value 'rainbow-5 palette)) (rainbow-6 (modus-themes--retrieve-palette-value 'rainbow-6 palette)) (rainbow-7 (modus-themes--retrieve-palette-value 'rainbow-7 palette)) (rainbow-8 (modus-themes--retrieve-palette-value 'rainbow-8 palette)) (bg-main (modus-themes--retrieve-palette-value 'bg-main palette)) (fg-main (modus-themes--retrieve-palette-value 'fg-main palette)) (bg-dim (modus-themes--retrieve-palette-value 'bg-dim palette)) (fg-dim (modus-themes--retrieve-palette-value 'fg-dim palette)) (bg-alt (modus-themes--retrieve-palette-value 'bg-alt palette)) (fg-alt (modus-themes--retrieve-palette-value 'fg-alt palette)) (bg-active (modus-themes--retrieve-palette-value 'bg-active palette)) (bg-inactive (modus-themes--retrieve-palette-value 'bg-inactive palette)) (border (modus-themes--retrieve-palette-value 'border palette)) (red (modus-themes--retrieve-palette-value 'red palette)) (red-warmer (modus-themes--retrieve-palette-value 'red-warmer palette)) (red-cooler (modus-themes--retrieve-palette-value 'red-cooler palette)) ...) (custom-theme-set-faces 'modus-alect-dark `(modus-themes-heading-0 (...)) `(modus-themes-heading-1 (...)) `(modus-themes-heading-2 (...)) `(modus-themes-heading-3 (...)) `(modus-themes-heading-4 (...)) `(modus-themes-heading-5 (...)) `(modus-themes-heading-6 (...)) `(modus-themes-heading-7 (...)) `(modus-themes-heading-8 (...)) `(modus-themes-completion-match-0 (...)) `(modus-themes-completion-match-1 (...)) `(modus-themes-completion-match-2 (...)) `(modus-themes-completion-match-3 (...)) `(modus-themes-completion-selected (...)) `(modus-themes-bold (...)) `(modus-themes-fixed-pitch (...)) `(modus-themes-slant (...)) `(modus-themes-ui-variable-pitch (...)) `(modus-themes-button (... ... ...)) `(modus-themes-prompt (...)) `(modus-themes-reset-soft (...)) `(default (...)) `(bold (...)) `(bold-italic (...)) `(underline (...)) `(italic (...)) `(cursor (...)) `(fringe (...)) `(menu (...)) `(scroll-bar (...)) `(tool-bar (...)) `(vertical-border (...)) `(abbrev-table-name (...)) `(appt-notification (...)) `(blink-matching-paren-offscreen (...)) `(buffer-menu-buffer (...)) ...) (custom-theme-set-variables 'modus-alect-dark `(ansi-color-faces-vector [default bold shadow italic underline success warning error]) `(ansi-color-names-vector ["#595959" ... ... ... ... ... ... "#a6a6a6"]) `(chart-face-color-list '...) `(exwm-floating-border-color ,border) `(highlight-changes-colors nil) `(highlight-changes-face-list '...) `(ibuffer-filter-group-name-face 'bold) `(ibuffer-title-face 'default) `(hl-todo-keyword-faces '...) `(pdf-view-midnight-colors '...) `(rustic-ansi-faces [... ... ... ... ... ... ... ...]) `(viper-replace-overlay-cursor-color ,err) `(viper-insert-state-cursor-color ,info) `(viper-emacs-state-cursor-color ,fg-main) `(xterm-color-names [... ... ... ... ... ... ... ...]) `(xterm-color-names-bright [... ... ... ... ... ... ... ...]) '(frame-background-mode 'dark))) :lexical)
  modus-themes-theme(modus-alect-dark modus-alect-themes "A dark theme in the modus family like alect-dark." dark ef-owl-palette modus-alect-palette nil)
...

It seems to me this call wants to be inside a let-wrapping environment like modus-with-colors, but of course that binds the colors of the currently active theme, not the theme we are creating.

If you change the name of the theme, sometimes these errors go away. And sometimes modus-themes-theme returns nil without error.

Summary

All in all it's quite a bit harder than I hoped to play around with deriving themes. The workflow I had imagined:

1. Pick a basic modus/ef/standard theme you like as a base theme.
2. Create a simple package defining your own custom palette.
3. Use modus-themes-theme to create your theme, deriving from your desired base theme's palette.
4. Load your newly created theme and test it.
5. Add a few more color mappings to your custom palette.
6. Maybe try updating the theme from which your new theme derives (say from modus-vivendi to ef-owl).
7. Keep evaluating modus-themes-theme after every change to update the theme (maybe requiring you to load-theme the theme again, ideally not).

Is this the kind of workflow that's intended?

Thanks for all your work on modus.

[protesilaos]

Thank you @jdtsmith for the detailed feedback and sorry for the trouble!

Is this the kind of workflow that's intended?

No, because I had not considered the scenario of picking a palette beyond those in modus-themes.el. Now that you mention though, I see no reason why such a restriction is relevant.

Before I proceed to review the kind of the changes needed to cover what you ask here, I was independently working on modus-themes-generate-palette (still a work in progress). It can be used to generate a palette based only on bg-main, fg-main, red, green, yellow, blue, magenta, and cyan values. Maybe this is easier?

Example:

(defvar modus-solarized-palette
  (modus-themes-generate-palette
   '((bg-main "#EEE8D5")
     (fg-main "#073642")
     (red "#DC322F")
     (green "#859900")
     (yellow "#B58900")
     (blue "#268BD2")
     (magenta "#D33682")
     (cyan "#2AA198"))))

(modus-themes-theme
 'modus-solarized
 'modus-solarized-themes
 "Proof-of-concept of a Modus Solarized theme."
 'light
 'modus-solarized-palette
 nil
 nil)

Again, this is a work-in-progress but may ultimately be the easier way forward for what you want to do. I can see modus-themes-generate-palette accepting an optional list of mappings as well.

[protesilaos]

I added the optional mappings to modus-themes-generate-palette. Here is a complete example with 8 solarized colors and then palette mappings that mostly taken from the standard-themes.el.

[ Again, I do not mean to distract from your original point, but maybe this addresses it indirectly. ]

A complete example:

(defvar modus-solarized-mappings-like-standard-dark
  '(
    ;; I am adding a few more to make the theme look better.
    (bg-mode-line-active bg-active)
    (fg-mode-line-active fg-main)
    (border-mode-line-active border)
    (bg-mode-line-inactive bg-dim)
    (fg-mode-line-inactive fg-dim)
    (border-mode-line-inactive border)

    (bg-region bg-active)
    (bg-paren-match bg-yellow-intense)
    (bg-hover bg-magenta-intense)
    (bg-hover-secondary bg-magenta-subtle)
    (bg-completion bg-yellow-subtle)
    (bg-hl-line bg-yellow-nuanced)

    ;; The rest comes for the standard-themes.el
    (cursor yellow-cooler)

    (name cyan-cooler)
    (keybind blue-cooler)

    (err red)
    (warning yellow-warmer)
    (info green)

;;;; Prompt mappings

    (fg-prompt blue)

;;;; Code mappings

    (builtin blue-faint)
    (comment red-warmer)
    (constant cyan-cooler)
    (fnname cyan-warmer)
    (fnname-call cyan-faint)
    (keyword cyan)
    (preprocessor blue-faint)
    (docstring yellow-cooler)
    (string yellow-cooler)
    (type green-cooler)
    (variable yellow)
    (variable-use yellow-faint)
    (rx-escape green) ; compare with `string'
    (rx-construct fg-main)

;;;; Accent mappings

    (accent-0 blue-warmer)
    (accent-1 red-cooler)
    (accent-2 green)
    (accent-3 magenta-cooler)

;;;; Link mappings

    (fg-link cyan)
    (bg-link unspecified)
    (underline-link blue-warmer)

    (fg-link-visited magenta-cooler)
    (bg-link-visited unspecified)
    (underline-link-visited magenta)

;;;; Mail mappings

    (mail-0 magenta-warmer)
    (mail-1 cyan-cooler)
    (mail-2 yellow)
    (mail-3 red)
    (mail-4 blue-warmer)
    (mail-recipient blue)
    (mail-subject magenta-cooler)
    (mail-other cyan)

    (bg-diff-context bg-dim)

    (fg-region unspecified)

    (fringe bg-dim)

    (docmarkup constant)
    (property variable)

    (date-common cyan-warmer)
    (date-deadline red)
    (date-event fg-alt)
    (date-holiday red-cooler)
    (date-now fg-main)
    (date-range fg-alt)
    (date-scheduled red-cooler)
    (date-weekday cyan-warmer)
    (date-weekend red)

    (bg-prompt unspecified)

    (fg-line-number-inactive fg-dim)
    (fg-line-number-active fg-main)
    (bg-line-number-inactive unspecified)
    (bg-line-number-active unspecified)

    (fg-completion-match-0 red-warmer)
    (fg-completion-match-1 cyan)
    (fg-completion-match-2 green-cooler)
    (fg-completion-match-3 magenta-cooler)

    (rainbow-1 blue-cooler)
    (rainbow-2 yellow-cooler)
    (rainbow-3 magenta-cooler)
    (rainbow-4 red-faint)
    (rainbow-5 green-warmer)
    (rainbow-6 cyan-cooler)
    (rainbow-7 blue-faint)
    (rainbow-8 magenta-warmer)

    (bg-tab-bar bg-alt)
    (bg-tab-current bg-main)
    (bg-tab-other bg-active)

    (bg-space unspecified)
    (fg-space border)
    (bg-space-err bg-red-intense)

    (bg-search-current bg-magenta-intense)
    (bg-search-lazy bg-cyan-intense)
    (bg-search-static bg-yellow-subtle)
    (bg-search-replace bg-red-intense)

    (bg-search-rx-group-0 bg-blue-intense)
    (bg-search-rx-group-1 bg-yellow-intense)
    (bg-search-rx-group-2 bg-green-subtle)
    (bg-search-rx-group-3 bg-magenta-subtle)

    (prose-code cyan-cooler)
    (prose-macro green-warmer)
    (prose-verbatim magenta-warmer)

    (fg-heading-0 rainbow-0)
    (fg-heading-1 rainbow-1)
    (fg-heading-2 rainbow-2)
    (fg-heading-3 rainbow-3)
    (fg-heading-4 rainbow-4)
    (fg-heading-5 rainbow-5)
    (fg-heading-6 rainbow-6)
    (fg-heading-7 rainbow-7)
    (fg-heading-8 rainbow-8)

    (bg-heading-0 unspecified)
    (bg-heading-1 unspecified)
    (bg-heading-2 unspecified)
    (bg-heading-3 unspecified)
    (bg-heading-4 unspecified)
    (bg-heading-5 unspecified)
    (bg-heading-6 unspecified)
    (bg-heading-7 unspecified)
    (bg-heading-8 unspecified)

    (overline-heading-0 unspecified)
    (overline-heading-1 unspecified)
    (overline-heading-2 unspecified)
    (overline-heading-3 unspecified)
    (overline-heading-4 unspecified)
    (overline-heading-5 unspecified)
    (overline-heading-6 unspecified)
    (overline-heading-7 unspecified)
    (overline-heading-8 unspecified)))

(defvar modus-solarized-palette
  (modus-themes-generate-palette
   '((bg-main "#073642")
     (fg-main "#EEE8D5")
     (red "#DC322F")
     (green "#859900")
     (yellow "#B58900")
     (blue "#268BD2")
     (magenta "#D33682")
     (cyan "#2AA198"))
   nil
   nil
   modus-solarized-mappings-like-standard-dark))

(modus-themes-theme
 'modus-solarized
 'modus-solarized-themes
 "Proof-of-concept of a Modus Solarized theme."
 'dark
 'modus-solarized-palette
 nil
 nil)

[jdtsmith]

Thanks, and no worries. I always thought your entire constellation of themes should derive from one parent source, and you came to the same conclusion on your own.

modus-themes-theme
 'modus-solarized
 'modus-solarized-themes
 "Proof-of-concept of a Modus Solarized theme."
 'dark
 'modus-solarized-palette
 nil
 nil)

I see, so deriving "from nothing"? That could be very interesting. For me though, I'm no theme expert. I don't know all of the possible package config, etc., and I don't know how modus mixes it's colors, so it feels much safer to start from a standard based theme that works relatively well, like standard-dark or ef-owl, then add my own flourishes, as needed. In general I think people will definitely like the idea of publishing themes that pick up from and build on your other excellent themes. These derived themes then get automatic improvements when your base theme improves.

I could use a large override list for this type of thing (maybe I should), but that seems less durable, and not shareable. But maybe your "generate palette" will read my mind ;).

I can see potential issues you might have if you let themes derive from any theme, so I'm sympathetic to the idea that there are only two "base themes" possible. But perhaps that should be spelled out in the docs (sorry if I missed it)?

Thanks again for all your work and apologies if this late night brain dump came off as overly critical.

[jdtsmith]

I can see modus-themes-generate-palette accepting an optional list of mappings as well.

Missed that. I think this could do what I want, though conceptually it would be hard to understand when straight derivation makes sense, and when generating from an input list of mappings does. They seem to be quite similar operations.

[protesilaos]

I have made a few more changes in the meantime. This seems to work:

;; Contents of NAME-theme.el in `custom-theme-load-path'.
(require 'standard-themes)

(load-theme 'standard-dark t t)

(defvar modus-standard-dark-palette
  (modus-themes-generate-palette
   ;; Here you add what is meant to differ from `standard-dark-palette'.
   '((bg-main "#202020")
     (fg-main "#d0d0d0")
     (cursor "#ffff00")
     (comment "#00ffff"))
   'cool
   standard-dark-palette))

(modus-themes-theme
 'modus-standard-dark-derivative
 'modus-standard-themes
 "Demo."
 'dark
 'standard-dark-palette
 'modus-standard-dark-palette
 nil)

I wish we could autoload a defvar so that you would not have to do load-theme and related just to get the dependency in place. But maybe this is not a big problem.

[protesilaos]

Thanks again for all your work and apologies if this late night brain dump came off as overly critical.

All good! I did not interpret it negatively, anyway. What I want is to make all this as useful/flexible as possible.

[jdtsmith]

Looks like a flexible approach. Is the generate-palette call required? I.e. can the modus-standard-dark-palette provide just a few "overrides"?

BTW it seems modus-themes-generate-palette uses color-blend, which will only be introduced in v31.