Include Haskell syntax file with minor modifications

This fixes #24

README.md

@@ -339,7 +339,7 @@ this to sending current paragraph. If this is happening you either:
 
 1. Opened a file without `.tidal` extension, or changed file type accidentally.
    *Solution*: Reopen Vim or set filetype for current buffer with `:set
-   ft=haskell.tidal`.
+   ft=tidal`.
 2. Have `g:tidal_no_mappings` setting on your `.vimrc`. This disables all
    mappings.
    *Solution*: Remove `<c-e>` binding, or rebind to something else.

ftdetect/tidal.vim

@@ -1 +1 @@
-autocmd BufRead,BufNewFile *.tidal setfiletype haskell.tidal
+autocmd BufRead,BufNewFile *.tidal setfiletype tidal

syntax/tidal.vim

@@ -0,0 +1,212 @@
+" syntax highlighting for tidal/haskell
+"
+" Very minor modifications from syntax file of
+" https://github.com/neovimhaskell/haskell-vim
+"
+" Heavily modified version of the haskell syntax
+" highlighter to support haskell.
+"
+" author: raichoo (raichoo@googlemail.com)
+
+if version < 600
+  syn clear
+elseif exists("b:current_syntax")
+  finish
+endif
+
+if get(g:, 'haskell_backpack', 0)
+  syn keyword haskellBackpackStructure unit signature
+  syn keyword haskellBackpackDependency dependency
+endif
+
+syn spell notoplevel
+syn match haskellRecordField contained containedin=haskellBlock
+  \ "[_a-z][a-zA-Z0-9_']*\(,\s*[_a-z][a-zA-Z0-9_']*\)*\_s\+::\_s"
+  \ contains=
+  \ haskellIdentifier,
+  \ haskellOperators,
+  \ haskellSeparator,
+  \ haskellParens
+syn match haskellTypeSig
+  \ "^\s*\(where\s\+\|let\s\+\|default\s\+\)\?[_a-z][a-zA-Z0-9_']*#\?\(,\s*[_a-z][a-zA-Z0-9_']*#\?\)*\_s\+::\_s"
+  \ contains=
+  \ haskellWhere,
+  \ haskellLet,
+  \ haskellDefault,
+  \ haskellIdentifier,
+  \ haskellOperators,
+  \ haskellSeparator,
+  \ haskellParens
+syn keyword haskellWhere where
+syn keyword haskellLet let
+syn match HaskellDerive "\<deriving\>\(\s\+\<\(anyclass\|instance\|newtype\|stock\)\>\)\?"
+syn keyword haskellDeclKeyword module class instance newtype in
+syn match haskellDecl "\<\(type\|data\)\>\s\+\(\<family\>\)\?"
+syn keyword haskellDefault default
+syn keyword haskellImportKeywords import qualified safe as hiding contained
+syn keyword haskellForeignKeywords foreign export import ccall safe unsafe interruptible capi prim contained
+syn region haskellForeignImport start="\<foreign\>" end="\_s\+::\s" keepend
+  \ contains=
+  \ haskellString,
+  \ haskellOperators,
+  \ haskellForeignKeywords,
+  \ haskellIdentifier
+syn match haskellImport "^\s*\<import\>\s\+\(\<safe\>\s\+\)\?\(\<qualified\>\s\+\)\?.\+\(\s\+\<as\>\s\+.\+\)\?\(\s\+\<hiding\>\)\?"
+  \ contains=
+  \ haskellParens,
+  \ haskellOperators,
+  \ haskellImportKeywords,
+  \ haskellType,
+  \ haskellLineComment,
+  \ haskellBlockComment,
+  \ haskellString,
+  \ haskellPragma
+syn keyword haskellKeyword do case of
+if get(g:, 'haskell_enable_static_pointers', 0)
+  syn keyword haskellStatic static
+endif
+syn keyword haskellConditional if then else
+syn match haskellNumber "\<[0-9]\+\>\|\<0[xX][0-9a-fA-F]\+\>\|\<0[oO][0-7]\+\>\|\<0[bB][10]\+\>"
+syn match haskellFloat "\<[0-9]\+\.[0-9]\+\([eE][-+]\=[0-9]\+\)\=\>"
+syn match haskellSeparator  "[,;]"
+syn region haskellParens matchgroup=haskellDelimiter start="(" end=")" contains=TOP,haskellTypeSig,@Spell
+syn region haskellBrackets matchgroup=haskellDelimiter start="\[" end="]" contains=TOP,haskellTypeSig,@Spell
+syn region haskellBlock matchgroup=haskellDelimiter start="{" end="}" contains=TOP,@Spell
+syn keyword haskellInfix infix infixl infixr
+syn keyword haskellBottom undefined error
+syn match haskellOperators "[-!#$%&\*\+/<=>\?@\\^|~:.]\+\|\<_\>"
+syn match haskellQuote "\<'\+" contained
+syn match haskellQuotedType "[A-Z][a-zA-Z0-9_']*\>" contained
+syn region haskellQuoted start="\<'\+" end="\>"
+  \ contains=
+  \ haskellType,
+  \ haskellQuote,
+  \ haskellQuotedType,
+  \ haskellSeparator,
+  \ haskellParens,
+  \ haskellOperators,
+  \ haskellIdentifier
+syn match haskellLineComment "---*\([^-!#$%&\*\+./<=>\?@\\^|~].*\)\?$"
+  \ contains=
+  \ haskellTodo,
+  \ @Spell
+syn match haskellBacktick "`[A-Za-z_][A-Za-z0-9_\.']*#\?`"
+syn region haskellString start=+"+ skip=+\\\\\|\\"+ end=+"+
+  \ contains=@Spell
+syn match haskellIdentifier "[_a-z][a-zA-z0-9_']*" contained
+syn match haskellChar "\<'[^'\\]'\|'\\.'\|'\\u[0-9a-fA-F]\{4}'\>"
+syn match haskellType "\<[A-Z][a-zA-Z0-9_']*\>"
+syn region haskellBlockComment start="{-" end="-}"
+  \ contains=
+  \ haskellBlockComment,
+  \ haskellTodo,
+  \ @Spell
+syn region haskellPragma start="{-#" end="#-}"
+syn region haskellLiquid start="{-@" end="@-}"
+"syn match haskellPreProc "^#.*$"
+syn keyword haskellTodo TODO FIXME contained
+" Treat a shebang line at the start of the file as a comment
+syn match haskellShebang "\%^#!.*$"
+if !get(g:, 'haskell_disable_TH', 0)
+    syn match haskellQuasiQuoted "." containedin=haskellQuasiQuote contained
+    syn region haskellQuasiQuote matchgroup=haskellTH start="\[[_a-zA-Z][a-zA-z0-9._']*|" end="|\]"
+    syn region haskellTHBlock matchgroup=haskellTH start="\[\(d\|t\|p\)\?|" end="|]" contains=TOP
+    syn region haskellTHDoubleBlock matchgroup=haskellTH start="\[||" end="||]" contains=TOP
+endif
+if get(g:, 'haskell_enable_typeroles', 0)
+  syn keyword haskellTypeRoles phantom representational nominal contained
+  syn region haskellTypeRoleBlock matchgroup=haskellTypeRoles start="type\s\+role" end="$" keepend
+    \ contains=
+    \ haskellType,
+    \ haskellTypeRoles
+endif
+if get(g:, 'haskell_enable_quantification', 0)
+  syn keyword haskellForall forall
+endif
+if get(g:, 'haskell_enable_recursivedo', 0)
+  syn keyword haskellRecursiveDo mdo rec
+endif
+if get(g:, 'haskell_enable_arrowsyntax', 0)
+  syn keyword haskellArrowSyntax proc
+endif
+if get(g:, 'haskell_enable_pattern_synonyms', 0)
+  syn keyword haskellPatternKeyword pattern
+endif
+
+highlight def link haskellBottom Macro
+highlight def link haskellTH Boolean
+highlight def link haskellIdentifier Identifier
+highlight def link haskellForeignKeywords Structure
+highlight def link haskellKeyword Keyword
+highlight def link haskellDefault Keyword
+highlight def link haskellConditional Conditional
+highlight def link haskellNumber Number
+highlight def link haskellFloat Float
+highlight def link haskellSeparator Delimiter
+highlight def link haskellDelimiter Delimiter
+highlight def link haskellInfix Keyword
+highlight def link haskellOperators Operator
+highlight def link haskellQuote Operator
+highlight def link haskellShebang Comment
+highlight def link haskellLineComment Comment
+highlight def link haskellBlockComment Comment
+highlight def link haskellPragma SpecialComment
+highlight def link haskellLiquid SpecialComment
+highlight def link haskellString String
+highlight def link haskellChar String
+highlight def link haskellBacktick Operator
+highlight def link haskellQuasiQuoted String
+highlight def link haskellTodo Todo
+"highlight def link haskellPreProc PreProc
+highlight def link haskellAssocType Type
+highlight def link haskellQuotedType Type
+highlight def link haskellType Type
+highlight def link haskellImportKeywords Include
+if get(g:, 'haskell_classic_highlighting', 0)
+  highlight def link haskellDeclKeyword Keyword
+  highlight def link HaskellDerive Keyword
+  highlight def link haskellDecl Keyword
+  highlight def link haskellWhere Keyword
+  highlight def link haskellLet Keyword
+else
+  highlight def link haskellDeclKeyword Structure
+  highlight def link HaskellDerive Structure
+  highlight def link haskellDecl Structure
+  highlight def link haskellWhere Structure
+  highlight def link haskellLet Structure
+endif
+
+if get(g:, 'haskell_enable_quantification', 0)
+  highlight def link haskellForall Operator
+endif
+if get(g:, 'haskell_enable_recursivedo', 0)
+  highlight def link haskellRecursiveDo Keyword
+endif
+if get(g:, 'haskell_enable_arrowsyntax', 0)
+  highlight def link haskellArrowSyntax Keyword
+endif
+if get(g:, 'haskell_enable_static_pointers', 0)
+  highlight def link haskellStatic Keyword
+endif
+if get(g:, 'haskell_classic_highlighting', 0)
+  if get(g:, 'haskell_enable_pattern_synonyms', 0)
+    highlight def link haskellPatternKeyword Keyword
+  endif
+  if get(g:, 'haskell_enable_typeroles', 0)
+    highlight def link haskellTypeRoles Keyword
+  endif
+else
+  if get(g:, 'haskell_enable_pattern_synonyms', 0)
+    highlight def link haskellPatternKeyword Structure
+  endif
+  if get(g:, 'haskell_enable_typeroles', 0)
+    highlight def link haskellTypeRoles Structure
+  endif
+endif
+
+if get(g:, 'haskell_backpack', 0)
+  highlight def link haskellBackpackStructure Structure
+  highlight def link haskellBackpackDependency Include
+endif
+
+let b:current_syntax = "tidal"