static/highlight/languages/haskell.js

   1 /*! `haskell` grammar compiled for Highlight.js 11.11.1 */
   2   (function(){
   3     var hljsGrammar = (function () {
   4   'use strict';
   5
   6   /*
   7   Language: Haskell
   8   Author: Jeremy Hull <sourdrums@gmail.com>
   9   Contributors: Zena Treep <zena.treep@gmail.com>
  10   Website: https://www.haskell.org
  11   Category: functional
  12   */
  13
  14   function haskell(hljs) {
  15
  16     /* See:
  17        - https://www.haskell.org/onlinereport/lexemes.html
  18        - https://downloads.haskell.org/ghc/9.0.1/docs/html/users_guide/exts/binary_literals.html
  19        - https://downloads.haskell.org/ghc/9.0.1/docs/html/users_guide/exts/numeric_underscores.html
  20        - https://downloads.haskell.org/ghc/9.0.1/docs/html/users_guide/exts/hex_float_literals.html
  21     */
  22     const decimalDigits = '([0-9]_*)+';
  23     const hexDigits = '([0-9a-fA-F]_*)+';
  24     const binaryDigits = '([01]_*)+';
  25     const octalDigits = '([0-7]_*)+';
  26     const ascSymbol = '[!#$%&*+.\\/<=>?@\\\\^~-]';
  27     const uniSymbol = '(\\p{S}|\\p{P})'; // Symbol or Punctuation
  28     const special = '[(),;\\[\\]`|{}]';
  29     const symbol = `(${ascSymbol}|(?!(${special}|[_:"']))${uniSymbol})`;
  30
  31     const COMMENT = { variants: [
  32       // Double dash forms a valid comment only if it's not part of legal lexeme.
  33       // See: Haskell 98 report: https://www.haskell.org/onlinereport/lexemes.html
  34       //
  35       // The commented code does the job, but we can't use negative lookbehind,
  36       // due to poor support by Safari browser.
  37       // > hljs.COMMENT(`(?<!${symbol})--+(?!${symbol})`, '$'),
  38       // So instead, we'll add a no-markup rule before the COMMENT rule in the rules list
  39       // to match the problematic infix operators that contain double dash.
  40       hljs.COMMENT('--+', '$'),
  41       hljs.COMMENT(
  42         /\{-/,
  43         /-\}/,
  44         { contains: [ 'self' ] }
  45       )
  46     ] };
  47
  48     const PRAGMA = {
  49       className: 'meta',
  50       begin: /\{-#/,
  51       end: /#-\}/
  52     };
  53
  54     const PREPROCESSOR = {
  55       className: 'meta',
  56       begin: '^#',
  57       end: '$'
  58     };
  59
  60     const CONSTRUCTOR = {
  61       className: 'type',
  62       begin: '\\b[A-Z][\\w\']*', // TODO: other constructors (build-in, infix).
  63       relevance: 0
  64     };
  65
  66     const LIST = {
  67       begin: '\\(',
  68       end: '\\)',
  69       illegal: '"',
  70       contains: [
  71         PRAGMA,
  72         PREPROCESSOR,
  73         {
  74           className: 'type',
  75           begin: '\\b[A-Z][\\w]*(\\((\\.\\.|,|\\w+)\\))?'
  76         },
  77         hljs.inherit(hljs.TITLE_MODE, { begin: '[_a-z][\\w\']*' }),
  78         COMMENT
  79       ]
  80     };
  81
  82     const RECORD = {
  83       begin: /\{/,
  84       end: /\}/,
  85       contains: LIST.contains
  86     };
  87
  88     const NUMBER = {
  89       className: 'number',
  90       relevance: 0,
  91       variants: [
  92         // decimal floating-point-literal (subsumes decimal-literal)
  93         { match: `\\b(${decimalDigits})(\\.(${decimalDigits}))?` + `([eE][+-]?(${decimalDigits}))?\\b` },
  94         // hexadecimal floating-point-literal (subsumes hexadecimal-literal)
  95         { match: `\\b0[xX]_*(${hexDigits})(\\.(${hexDigits}))?` + `([pP][+-]?(${decimalDigits}))?\\b` },
  96         // octal-literal
  97         { match: `\\b0[oO](${octalDigits})\\b` },
  98         // binary-literal
  99         { match: `\\b0[bB](${binaryDigits})\\b` }
 100       ]
 101     };
 102
 103     return {
 104       name: 'Haskell',
 105       aliases: [ 'hs' ],
 106       keywords:
 107         'let in if then else case of where do module import hiding '
 108         + 'qualified type data newtype deriving class instance as default '
 109         + 'infix infixl infixr foreign export ccall stdcall cplusplus '
 110         + 'jvm dotnet safe unsafe family forall mdo proc rec',
 111       unicodeRegex: true,
 112       contains: [
 113         // Top-level constructions.
 114         {
 115           beginKeywords: 'module',
 116           end: 'where',
 117           keywords: 'module where',
 118           contains: [
 119             LIST,
 120             COMMENT
 121           ],
 122           illegal: '\\W\\.|;'
 123         },
 124         {
 125           begin: '\\bimport\\b',
 126           end: '$',
 127           keywords: 'import qualified as hiding',
 128           contains: [
 129             LIST,
 130             COMMENT
 131           ],
 132           illegal: '\\W\\.|;'
 133         },
 134         {
 135           className: 'class',
 136           begin: '^(\\s*)?(class|instance)\\b',
 137           end: 'where',
 138           keywords: 'class family instance where',
 139           contains: [
 140             CONSTRUCTOR,
 141             LIST,
 142             COMMENT
 143           ]
 144         },
 145         {
 146           className: 'class',
 147           begin: '\\b(data|(new)?type)\\b',
 148           end: '$',
 149           keywords: 'data family type newtype deriving',
 150           contains: [
 151             PRAGMA,
 152             CONSTRUCTOR,
 153             LIST,
 154             RECORD,
 155             COMMENT
 156           ]
 157         },
 158         {
 159           beginKeywords: 'default',
 160           end: '$',
 161           contains: [
 162             CONSTRUCTOR,
 163             LIST,
 164             COMMENT
 165           ]
 166         },
 167         {
 168           beginKeywords: 'infix infixl infixr',
 169           end: '$',
 170           contains: [
 171             hljs.C_NUMBER_MODE,
 172             COMMENT
 173           ]
 174         },
 175         {
 176           begin: '\\bforeign\\b',
 177           end: '$',
 178           keywords: 'foreign import export ccall stdcall cplusplus jvm '
 179                     + 'dotnet safe unsafe',
 180           contains: [
 181             CONSTRUCTOR,
 182             hljs.QUOTE_STRING_MODE,
 183             COMMENT
 184           ]
 185         },
 186         {
 187           className: 'meta',
 188           begin: '#!\\/usr\\/bin\\/env\ runhaskell',
 189           end: '$'
 190         },
 191         // "Whitespaces".
 192         PRAGMA,
 193         PREPROCESSOR,
 194
 195         // Literals and names.
 196
 197         // Single characters.
 198         {
 199           scope: 'string',
 200           begin: /'(?=\\?.')/,
 201           end: /'/,
 202           contains: [
 203             {
 204               scope: 'char.escape',
 205               match: /\\./,
 206             },
 207           ]
 208         },
 209         hljs.QUOTE_STRING_MODE,
 210         NUMBER,
 211         CONSTRUCTOR,
 212         hljs.inherit(hljs.TITLE_MODE, { begin: '^[_a-z][\\w\']*' }),
 213         // No markup, prevents infix operators from being recognized as comments.
 214         { begin: `(?!-)${symbol}--+|--+(?!-)${symbol}`},
 215         COMMENT,
 216         { // No markup, relevance booster
 217           begin: '->|<-' }
 218       ]
 219     };
 220   }
 221
 222   return haskell;
 223
 224 })();
 225
 226     hljs.registerLanguage('haskell', hljsGrammar);
 227   })();