From e3d0c0aee80422182d70856a3017e227d9fd42b4 Mon Sep 17 00:00:00 2001
From: Jonathan Chan <jonathanhwchan@gmail.com>
Date: Sun, 15 Dec 2019 22:57:31 -0800
Subject: [PATCH] =?UTF-8?q?Use=20specialized=20not-equals=20functions=20(!?=
 =?UTF-8?q?=3D,=20nchar=3D=3F)=20instead=20of=20general=20neq=3F=20functio?=
 =?UTF-8?q?n.?=

---
 lib.rkt    |  8 ++++----
 src/04.rkt | 10 +++++-----
 src/08.rkt |  2 +-
 src/11.rkt |  2 +-
 4 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/lib.rkt b/lib.rkt
index 37fe1e7..83cbfb4 100644
--- a/lib.rkt
+++ b/lib.rkt
@@ -21,7 +21,7 @@
          uncurry
 
          sum
-         != neq?
+         != nchar=?
          nzero?
          negate
          pos-or-zero
@@ -122,9 +122,9 @@
 (define (!= n1 n2)
   (not (= n1 n2)))
 
-;; neq : any -> any -> boolean
-(define (neq? v1 v2)
-  (not (eq? v1 v2)))
+;; nchar=? : char -> char -> boolean
+(define (nchar=? c1 c2)
+  (not (char=? c1 c2)))
 
 ;; nzero? : number -> boolean
 (define (nzero? n)
diff --git a/src/04.rkt b/src/04.rkt
index 047f8a0..8351b0c 100644
--- a/src/04.rkt
+++ b/src/04.rkt
@@ -19,12 +19,12 @@
 (define (has-group-of-two? cs)
   (cond [(< (length cs) 2) #f]
         [(= (length cs) 2)
-         (eq? (first cs) (second cs))]
+         (char=? (first cs) (second cs))]
         [else
-         (or (and (eq? (first cs)
-                       (second cs))
-                  (neq? (second cs)
-                        (third cs)))
+         (or (and (char=? (first cs)
+                          (second cs))
+                  (nchar=? (second cs)
+                           (third cs)))
              (has-group-of-two? (dropf cs (λ (c) (eq? c (first cs))))))]))
 
 (define-values (part1 part2)
diff --git a/src/08.rkt b/src/08.rkt
index 6233524..a789a7d 100644
--- a/src/08.rkt
+++ b/src/08.rkt
@@ -25,7 +25,7 @@
     (* ones twos)))
 
 (define part2
-  (let* ([image (map (∂ findf (∂ neq? #\2)) (transpose layers))])
+  (let* ([image (map (∂ findf (∂ nchar=? #\2)) (transpose layers))])
     (show-list-grid pixel-hash (chunks-of image width))))
 
 (show-solution part1 #f)
\ No newline at end of file
diff --git a/src/11.rkt b/src/11.rkt
index 9232a8e..3cf3713 100644
--- a/src/11.rkt
+++ b/src/11.rkt
@@ -53,7 +53,7 @@
         (let*-values
             ([(clr* st) (resume-with-output (resume clr))]
              [(δ st)    (resume-with-output st)])
-          (cond [(neq? clr clr*)
+          (cond [(!= clr clr*)
                  (hash-set! hull xy clr*)])
           (let* ([dir (update-dir dir δ)]
                  [xy  (update-pos dir xy)])