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(define-module (output general)
)
;; Returns a color with good contrast to the given background color.
(define-public (calculate-fg-color c)
(define (str->num c n) (string->number (substring/shared c n (+ n 2)) 16))
(let ((r (str->num c 1))
(g (str->num c 3))
(b (str->num c 5)))
(if (< 1/2 (/ (+ (* 0.299 r)
(* 0.587 g)
(* 0.144 b))
#xFF))
"#000000" "#e5e8e6")))
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