The GHC has several language extensions for numeric literals:
BinaryLiterals(e.g. 0b1100) Since GHC 7.10HexFloatLiterals(e.g. 0x1fff.50ffp3) Since GHC 8.4NumericUnderscores(e.g. 1_000_000) Since GHC 8.6
Here is the latest specification about them.
If you need syntax highlighting about them, you can use the following definitions in each editors etc. I prepared two kinds of fast version and exact version.
- Fast version: Pattern matching is approximate, but the response of the editor is fast.
- Exact version: Pattern matching is accurate. You can check the lexers on your editor in real time without compiling.
- Vim
- Emacs
- haskell-mode
- Atom (and Linguist)
- language-haskell package
- Visual Studio Code
- language-haskell extension
- Sublime Text 3
- SublimeHaskell
- Pygments
Substituting syntax/haskell.vim as follows:
-syn match hsNumber "\<[0-9]\+\>\|\<0[xX][0-9a-fA-F]\+\>\|\<0[oO][0-7]\+\>"
-syn match hsFloat "\<[0-9]\+\.[0-9]\+\([eE][-+]\=[0-9]\+\)\=\>"
+syn match hsNumber "\v<[0-9][0-9_]*>|<0[xX][0-9a-fA-F_]+>|<0[oO][0-7_]+>|<0[bB][01_]+>"
+syn match hsFloat "\v<[0-9][0-9_]*%(\.[0-9_]+%([eE][-+]?[0-9_]+)?>|[eE][-+]?[0-9_]+)>|<0[xX][0-9a-fA-F_]+%(\.[0-9a-fA-F_]+%([pP][-+]?[0-9_]+)?>|[pP][-+]?[0-9_]+)>"It has already been officially implemented. Since patch 8.0.1401
Substituting syntax/haskell.vim as follows:
-syn match hsNumber "\<[0-9]\+\>\|\<0[xX][0-9a-fA-F]\+\>\|\<0[oO][0-7]\+\>"
-syn match hsFloat "\<[0-9]\+\.[0-9]\+\([eE][-+]\=[0-9]\+\)\=\>"
+syn match hsNumber "\v<[0-9]%(_*[0-9])*>|<0[xX]_*[0-9a-fA-F]%(_*[0-9a-fA-F])*>|<0[oO]_*%(_*[0-7])*>|<0[bB]_*[01]%(_*[01])*>"
+syn match hsFloat "\v<[0-9]%(_*[0-9])*\.[0-9]%(_*[0-9])*%(_*[eE][-+]?[0-9]%(_*[0-9])*)?>|<[0-9]%(_*[0-9])*_*[eE][-+]?[0-9]%(_*[0-9])*>|<0[xX]_*[0-9a-fA-F]%(_*[0-9a-fA-F])*\.[0-9a-fA-F]%(_*[0-9a-fA-F])*%(_*[pP][-+]?[0-9]%(_*[0-9])*)?>|<0[xX]_*[0-9a-fA-F]%(_*[0-9a-fA-F])*_*[pP][-+]?[0-9]%(_*[0-9])*>"haskell-mode for Emacs
The definition files are haskell-lexeme.el and haskell-font-lock.el.
Lowercase literals are already almost correctly displayed.
In the current implementation, numeric literals are not highlighted. It would be slow and complicated to implement correctly.
language-haskell for Atom and Linguist
It has already been officially implemented. Since 1.15.0 and linguist 6.0.0
After making the following substitution, execute make command in the top directory.
Substituting src/include/repository.coffee as follows:
lit_num: [
name: 'constant.numeric.hexfloat.haskell'
- match: "0[xX]#{floatPattern('[0-9a-fA-F_]','[pP]')}"
+ match: "0[xX]_*#{floatPattern('[0-9a-fA-F]','[pP]')}"
,
name: 'constant.numeric.hexadecimal.haskell'
- match: '0[xX][_0-9a-fA-F]+'
+ match: '0[xX]_*[0-9a-fA-F](_*[0-9a-fA-F])*'
,
name: 'constant.numeric.octal.haskell'
- match: '0[oO][_0-7]+'
+ match: '0[oO]_*[0-7](_*[0-7])*'
,
name: 'constant.numeric.binary.haskell'
- match: '0[bB][_01]+'
+ match: '0[bB]_*[01](_*[01])*'
,
name: 'constant.numeric.float.haskell'
- match: "[0-9]#{floatPattern('[0-9_]', '[eE]')}"
+ match: "#{floatPattern('[0-9]', '[eE]')}"
,
name: 'constant.numeric.decimal.haskell'
- match: '[0-9][_0-9]*'
+ match: '[0-9](_*[0-9])*'
]Furthermore, substituting src/include/util.coffee as follows:
floatPattern = (digit, exp) ->
- exponent = "#{exp}[+-]?[0-9_]+"
- "#{digit}*(?:\\.#{digit}+(?:#{exponent})?|#{exponent})"
+ u_digits = "#{digit}(_*#{digit})*"
+ exponent = "_*#{exp}[+-]?[0-9](_*[0-9])*"
+ "#{u_digits}(?:\\.#{u_digits}(?:#{exponent})?|#{exponent})"Let's use the exact version.
It has already been officially implemented. Here
Substituting syntaxes/haskell.tmLanguage as follows:
<key>match</key>
- <string>\b([0-9]+\.[0-9]+([eE][+-]?[0-9]+)?|[0-9]+[eE][+-]?[0-9]+)\b</string>
+ <string>\b([0-9](_*[0-9])*\.[0-9](_*[0-9])*(_*[eE][-+]?[0-9](_*[0-9])*)?|[0-9](_*[0-9])*_*[eE][-+]?[0-9](_*[0-9])*|0[xX]_*[0-9a-fA-F](_*[0-9a-fA-F])*\.[0-9a-fA-F](_*[0-9a-fA-F])*(_*[pP][-+]?[0-9](_*[0-9])*)?|0[xX]_*[0-9a-fA-F](_*[0-9a-fA-F])*_*[pP][-+]?[0-9](_*[0-9])*)\b</string>
<key>name</key>
<string>constant.numeric.float.haskell</string>
</dict>
<dict>
<key>match</key>
- <string>\b([0-9]+|0([xX][0-9a-fA-F]+|[oO][0-7]+))\b</string>
+ <string>\b([0-9](_*[0-9])*|0([xX]_*[0-9a-fA-F](_*[0-9a-fA-F])*|[oO]_*[0-7](_*[0-7])*|[bB]_*[01](_*[01])*))\b</string>It has already been officially implemented by B. Scott Michel. Since 2.1.23
I will not prepare. Let's use the exact version.
Substituting pygments/lexers/haskell.py as follows:
# Numbers
- (r'\d+[eE][+-]?\d+', Number.Float),
- (r'\d+\.\d+([eE][+-]?\d+)?', Number.Float),
- (r'0[oO][0-7]+', Number.Oct),
- (r'0[xX][\da-fA-F]+', Number.Hex),
- (r'\d+', Number.Integer),
+ (r'0[xX]_*[\da-fA-F](_*[\da-fA-F])*_*[pP][+-]?\d(_*\d)*', Number.Float),
+ (r'0[xX]_*[\da-fA-F](_*[\da-fA-F])*\.[\da-fA-F](_*[\da-fA-F])*(_*[pP][+-]?\d(_*\d)*)?', Number.Float),
+ (r'\d(_*\d)*_*[eE][+-]?\d(_*\d)*', Number.Float),
+ (r'\d(_*\d)*\.\d(_*\d)*(_*[eE][+-]?\d(_*\d)*)?', Number.Float),
+ (r'0[bB]_*[01](_*[01])*', Number.Bin),
+ (r'0[oO]_*[0-7](_*[0-7])*', Number.Oct),
+ (r'0[xX]_*[\da-fA-F](_*[\da-fA-F])*', Number.Hex),
+ (r'\d(_*\d)*', Number.Integer),
# Character/String Literals
React
Typescript
Django
Laravel
Facebook
Microsoft
Google
Alibaba
D3
Tencent