Optimize comparisons to chars

Author: miniBill

src/Elm/Parser/Comments.elm

@@ -10,7 +10,17 @@ singleLineComment : ParserFast.Parser (Node String)
 singleLineComment =
     ParserFast.symbolFollowedBy "--"
         (ParserFast.whileMapWithRange
-            (\c -> c /= '\u{000D}' && c /= '\n' && not (Char.Extra.isUtf16Surrogate c))
+            (\c ->
+                case c of
+                    '\u{000D}' ->
+                        False
+
+                    '\n' ->
+                        False
+
+                    _ ->
+                        not (Char.Extra.isUtf16Surrogate c)
+            )
             (\range content ->
                 Node
                     { start = { row = range.start.row, column = range.start.column - 2 }

src/Elm/Parser/Expose.elm

@@ -79,8 +79,34 @@ infixExpose =
         )
         (ParserFast.symbolFollowedBy "("
             (ParserFast.ifFollowedByWhileWithoutLinebreak
-                (\c -> c /= ')' && c /= '\n' && c /= ' ')
-                (\c -> c /= ')' && c /= '\n' && c /= ' ')
+                (\c ->
+                    case c of
+                        ')' ->
+                            False
+
+                        '\n' ->
+                            False
+
+                        ' ' ->
+                            False
+
+                        _ ->
+                            True
+                )
+                (\c ->
+                    case c of
+                        ')' ->
+                            False
+
+                        '\n' ->
+                            False
+
+                        ' ' ->
+                            False
+
+                        _ ->
+                            True
+                )
             )
         )
         Tokens.parensEnd

src/Elm/Parser/Tokens.elm

@@ -243,7 +243,19 @@ singleQuotedStringLiteralAfterDoubleQuote =
     ParserFast.loopUntil (ParserFast.symbol "\"" ())
         (ParserFast.oneOf2
             (ParserFast.symbolFollowedBy "\\" (escapedCharValueMap String.fromChar))
-            (ParserFast.whileWithoutLinebreak (\c -> c /= '"' && c /= '\\' && not (Char.Extra.isUtf16Surrogate c)))
+            (ParserFast.whileWithoutLinebreak
+                (\c ->
+                    case c of
+                        '"' ->
+                            False
+
+                        '\\' ->
+                            False
+
+                        _ ->
+                            not (Char.Extra.isUtf16Surrogate c)
+                )
+            )
         )
         ""
         (\extension soFar ->
@@ -258,7 +270,19 @@ tripleQuotedStringLiteralOfterTripleDoubleQuote =
         (ParserFast.oneOf3
             (ParserFast.symbol "\"" "\"")
             (ParserFast.symbolFollowedBy "\\" (escapedCharValueMap String.fromChar))
-            (ParserFast.while (\c -> c /= '"' && c /= '\\' && not (Char.Extra.isUtf16Surrogate c)))
+            (ParserFast.while
+                (\c ->
+                    case c of
+                        '"' ->
+                            False
+
+                        '\\' ->
+                            False
+
+                        _ ->
+                            not (Char.Extra.isUtf16Surrogate c)
+                )
+            )
         )
         ""
         (\extension soFar ->

src/Elm/Writer.elm

@@ -572,13 +572,20 @@ writeChar c =
     let
         escape : String
         escape =
-            if c == '\t' || c == '\'' || c == '\\' then
-                "\\"
+            case c of
+                '\t' ->
+                    "'\\"
 
-            else
-                ""
+                '\'' ->
+                    "'\\"
+
+                '\\' ->
+                    "'\\"
+
+                _ ->
+                    "'"
     in
-    string ("'" ++ escape ++ String.fromChar c ++ "'")
+    string (escape ++ String.fromChar c ++ "'")
 
 
 {-| Write a pattern