[elpa] externals/ef-themes 9bbb2fb45e 3/7: Include point of entry for shared overrides (extend b3e1a72)

[ELPA Syncer]

branch: externals/ef-themes
commit 9bbb2fb45ee9c3ebcfc8458ca4a1850a123dcb6b
Author: Protesilaos Stavrou <info@protesilaos.com>
Commit: Protesilaos Stavrou <info@protesilaos.com>

    Include point of entry for shared overrides (extend b3e1a72)
---
 README.org   | 10 +++++++++-
 ef-themes.el | 13 ++++++++++++-
 2 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/README.org b/README.org
index 4da2e4d01c..1f265dc8ff 100644
--- a/README.org
+++ b/README.org
@@ -423,7 +423,9 @@ Other examples:
 :END:
 #+cindex: Override color values and semantic color mappings
 
-[ Part of {{{development-version}}}. ]
+[ Part of {{{development-version}}}.  For a video demo of the same
+idea that I implemented in the ~modus-themes~, check:
+https://protesilaos.com/codelog/2022-12-17-modus-themes-v4-demo/. ]
 
 Each theme defines its own color palette as well as semantic color
 mappings.  The former is the set of color values such as what shade of
@@ -437,6 +439,12 @@ The definition is stored in the variable 
=ef-NAME-palette=, where
 ~ef-summer~ theme.  Overrides for those associations are specified in
 the variable =ef-NAME-palette-overrides=.
 
+#+vindex: ef-themes-common-palette-overrides
+The variable ~ef-themes-common-palette-overrides~ is available for
+shared values.  It is advised to only use this for mappings that do
+not specify a color value directly.  This way, the text remains
+legible by getting the theme-specific color value it needs.
+
 All associations take the form of =(KEY VALUE)= pairs.  For example,
 the ~ef-summer-palette~ contains =(blue-warmer "#5250ef")=.  Semantic
 color mappings are the same, though the =VALUE= is one of the named
diff --git a/ef-themes.el b/ef-themes.el
index b37ce941cc..59873ad1c2 100644
--- a/ef-themes.el
+++ b/ef-themes.el
@@ -1969,6 +1969,17 @@ Helper function for `ef-themes-preview-colors'."
 
 ;;;; Instantiate an Ef theme
 
+(defvar ef-themes-common-palette-overrides nil
+  "Set palette overrides for all the Modus themes.
+
+Mirror the elements of a theme's palette, overriding their value.
+The palette variables are named THEME-NAME-palette, while
+individual theme overrides are THEME-NAME-palette-overrides.  The
+THEME-NAME is one of the symbols in `modus-themes-items'.
+
+Individual theme overrides take precedence over these common
+overrides.")
+
 ;;;###autoload
 (defmacro ef-themes-theme (name palette &optional overrides)
   "Bind NAME's color PALETTE around face specs and variables.
@@ -1983,7 +1994,7 @@ corresponding entries."
   (let ((sym (gensym))
         (colors (mapcar #'car (symbol-value palette))))
     `(let* ((c '((class color) (min-colors 256)))
-            (,sym (append ,overrides ,palette))
+            (,sym (append ,overrides ef-themes-common-palette-overrides 
,palette))
             ,@(mapcar (lambda (color)
                         (list color
                               `(let* ((value (car (alist-get ',color ,sym))))