[elpa] externals/ement 6fc2908868 15/19: Tidy: Compilation warning

[ELPA Syncer]

branch: externals/ement
commit 6fc290886832f6bef914eb46155e08f08ef1d5f0
Author: Adam Porter <adam@alphapapa.net>
Commit: Adam Porter <adam@alphapapa.net>

    Tidy: Compilation warning
---
 ement-lib.el | 39 ++++++++++++++++++++-------------------
 1 file changed, 20 insertions(+), 19 deletions(-)

diff --git a/ement-lib.el b/ement-lib.el
index 3b1024e6fd..8bfad5e1fd 100644
--- a/ement-lib.el
+++ b/ement-lib.el
@@ -95,7 +95,7 @@ that stray such forms don't remain if the function is 
removed."
 
 ;; Copied from Emacs 28.  See 
<https://github.com/alphapapa/ement.el/issues/99>.
 
-;; FIXME: Remove this workaround when possible.
+;; TODO(future): Remove these workarounds when dropping support for Emacs <28.
 
 (eval-and-compile
   (unless (boundp 'color-luminance-dark-limit)
@@ -108,27 +108,28 @@ determined experimentally.")))
 (defalias 'ement--color-dark-p
   (if (fboundp 'color-dark-p)
       'color-dark-p
-    (lambda (rgb)
-      "Whether RGB is more readable against white than black.
+    (with-suppressed-warnings ((free-vars ement--color-luminance-dark-limit))
+      (lambda (rgb)
+        "Whether RGB is more readable against white than black.
 RGB is a 3-element list (R G B), each component in the range [0,1].
 This predicate can be used both for determining a suitable (black or white)
 contrast colour with RGB as background and as foreground."
-      (unless (<= 0 (apply #'min rgb) (apply #'max rgb) 1)
-        (error "RGB components %S not in [0,1]" rgb))
-      ;; Compute the relative luminance after gamma-correcting (assuming sRGB),
-      ;; and compare to a cut-off value determined experimentally.
-      ;; See https://en.wikipedia.org/wiki/Relative_luminance for details.
-      (let* ((sr (nth 0 rgb))
-             (sg (nth 1 rgb))
-             (sb (nth 2 rgb))
-             ;; Gamma-correct the RGB components to linear values.
-             ;; Use the power 2.2 as an approximation to sRGB gamma;
-             ;; it should be good enough for the purpose of this function.
-             (r (expt sr 2.2))
-             (g (expt sg 2.2))
-             (b (expt sb 2.2))
-             (y (+ (* r 0.2126) (* g 0.7152) (* b 0.0722))))
-        (< y ement--color-luminance-dark-limit)))))
+        (unless (<= 0 (apply #'min rgb) (apply #'max rgb) 1)
+          (error "RGB components %S not in [0,1]" rgb))
+        ;; Compute the relative luminance after gamma-correcting (assuming 
sRGB),
+        ;; and compare to a cut-off value determined experimentally.
+        ;; See https://en.wikipedia.org/wiki/Relative_luminance for details.
+        (let* ((sr (nth 0 rgb))
+               (sg (nth 1 rgb))
+               (sb (nth 2 rgb))
+               ;; Gamma-correct the RGB components to linear values.
+               ;; Use the power 2.2 as an approximation to sRGB gamma;
+               ;; it should be good enough for the purpose of this function.
+               (r (expt sr 2.2))
+               (g (expt sg 2.2))
+               (b (expt sb 2.2))
+               (y (+ (* r 0.2126) (* g 0.7152) (* b 0.0722))))
+          (< y ement--color-luminance-dark-limit))))))
 
 ;;;; Functions