indentation: fix some issues

README.md

@@ -31,33 +31,45 @@ Be sure that the following lines are in your
 
 To configure indentation in `purescript-vim` you can use the following variables:
 
-* `let g:purescript_indent_if = 3`
+* `let purescript_indent_if = 3`
 
         if bool
         >>>then ...
         >>>else ...
 
-* `let g:purescript_indent_case = 5`
+* `let purescript_indent_case = 5`
 
         case xs of
         >>>>>[]     -> ...
         >>>>>(y:ys) -> ...
 
-* `let g:purescript_indent_let = 4`
+* `let purescript_indent_let = 4`
 
         let x = 0 in
         >>>>x
 
-* `let g:purescript_indent_where = 6`
+* `let purescript_indent_where = 6`
 
         where f :: Int -> Int
         >>>>>>f x = x
 
-* `let g:purescript_indent_do = 3`
+* `let purescript_indent_do = 3`
 
         do x <- a
         >>>y <- b
 
+* `let purescript_indent_in = 1`
+
+	let x = 0
+	>in x
+
+* `let purescript_indent_dot = v:true`
+
+	unsnoc
+	  :: forall a
+	  >. List a
+	  -> Maybe (List a, a)
+
 
 [Purescript]: http://www.purescript.org
 [Pathogen]: https://github.com/tpope/vim-pathogen

indent/purescript.vim

@@ -65,8 +65,10 @@ setlocal indentexpr=GetPurescriptIndent()
 setlocal indentkeys=!^F,o,O,},=where,=in,=::,=->,==>
 
 function! GetPurescriptIndent()
+  let ppline = getline(v:lnum - 2)
   let prevline = getline(v:lnum - 1)
   let line = getline(v:lnum)
+  let synStackP = map(synstack(v:lnum - 1, col(".")), { key, val -> synIDattr(val, "name") })
 
   if line =~ '^\s*\<where\>'
     let s = match(prevline, '\S')
@@ -85,17 +87,35 @@ function! GetPurescriptIndent()
     return s + g:purescript_indent_in
   endif
 
-  let s = match(prevline, '^\s*\zs\(--\|import\>\)')
+  let s = match(prevline, '^\s*\zs\(--\|import\)')
   if s >= 0
+    " comments
+    " imports
+    return s
+  endif
+
+  if prevline =~ '^\S.*::' && line !~ '^\s*\(\.\|->\|=>\)' && !~ '^instance'
+    " f :: String
+    "	-> String
+    return 0
+  endif
+
+  let s = match(prevline, '[[:alnum:][:blank:]]\@<=|[[:alnum:][:blank:]$]')
+  if s >= 0 && index(synStackP, "purescriptFunctionDecl") == -1
+    " ident pattern quards but not if we are in a type declaration
+    " what we detect using syntax groups
     return s
   endif
 
   if prevline =~ '^\S'
-    " starting type signature or function body on next line
-    echom "xxx " . prevline
+    " starting type signature, function body, data & newtype on next line
     return &shiftwidth
   endif
 
+  if ppline =~ '^\S' && prevline =~ '^\s*$'
+    return 0
+  endif
+
   if line =~ '^\s*::'
     return match(prevline, '\S') + &shiftwidth
   endif
@@ -107,7 +127,6 @@ function! GetPurescriptIndent()
   let s = match(prevline, '^\s*\zs\%(::\|=>\|->\)')
   let r = match(prevline, '^\s*\zs\.')
   if s >= 0 || r >= 0
-    echom prevline
     if s >= 0
       if line !~ '^\s*\%(::\|=>\|->\)'
 	return s - 2
@@ -138,6 +157,7 @@ function! GetPurescriptIndent()
   endif
 
   if prevline =~ '[{([][^})\]]\+$'
+    echom "return 1"
     return match(prevline, '[{([]')
   endif
 
@@ -162,6 +182,7 @@ function! GetPurescriptIndent()
   endif
 
   if prevline =~ '[{([]\s*$'
+    echom "return 2"
     return match(prevline, '\S') + (line !~ '^\s*[})]]' ? 0 : &shiftwidth)
   endif
 
@@ -185,7 +206,7 @@ function! GetPurescriptIndent()
     return match(prevline, '\<data\>') + &shiftwidth
   endif
 
-  if (line =~ '^\s*}\s*' && prevline !~ '^\s*;')
+  if prevline =~ '^\s*[}\]]'
     return match(prevline, '\S') - &shiftwidth
   endif
 

syntax/purescript.vim

@@ -63,16 +63,27 @@ syn match purescriptImportParams "hiding" contained
   \ nextgroup=purescriptModuleParams,purescriptImportParams skipwhite
 
 " Function declaration
-syn region purescriptFunctionDecl excludenl start="^\z(\s*\)\(foreign\s\+import\_s\+\)\?[_a-z]\(\w\|\'\)*\_s\{-}\(::\|∷\)" end="^\z1\=\S"me=s-1,re=s-1 keepend
+syn region purescriptFunctionDecl
+  \ excludenl start="^\z(\s*\)\(\(foreign\s\+import\)\_s\+\)\?[_a-z]\(\w\|\'\)*\_s\{-}\(::\|∷\)"
+  \ end="^\z1\=\S"me=s-1,re=s-1 keepend
   \ contains=purescriptFunctionDeclStart,purescriptForall,purescriptOperatorType,purescriptOperatorTypeSig,purescriptType,purescriptTypeVar,purescriptDelimiter,@purescriptComment
-syn match purescriptFunctionDeclStart "^\s*\(foreign\s\+import\_s\+\)\?\([_a-z]\(\w\|\'\)*\)\_s\{-}\(::\|∷\)" contained
-  \ contains=purescriptImportKeyword,purescriptFunction,purescriptOperatorType
+syn region purescriptFunctionDecl
+  \ excludenl start="^\z(\s*\)where\z(\s\+\)[_a-z]\(\w\|\'\)*\_s\{-}\(::\|∷\)"
+  \ end="^\(\z1\s\{5}\z2\)\=\S"me=s-1,re=s-1 keepend
+  \ contains=purescriptFunctionDeclStart,purescriptForall,purescriptOperatorType,purescriptOperatorTypeSig,purescriptType,purescriptTypeVar,purescriptDelimiter,@purescriptComment
+syn region purescriptFunctionDecl
+  \ excludenl start="^\z(\s*\)let\z(\s\+\)[_a-z]\(\w\|\'\)*\_s\{-}\(::\|∷\)"
+  \ end="^\(\z1\s\{3}\z2\)\=\S"me=s-1,re=s-1 keepend
+  \ contains=purescriptFunctionDeclStart,purescriptForall,purescriptOperatorType,purescriptOperatorTypeSig,purescriptType,purescriptTypeVar,purescriptDelimiter,@purescriptComment
+syn match purescriptFunctionDeclStart "^\s*\(\(foreign\s\+import\|let\|where\)\_s\+\)\?\([_a-z]\(\w\|\'\)*\)\_s\{-}\(::\|∷\)" contained
+  \ contains=purescriptImportKeyword,purescriptWhere,purescriptLet,purescriptFunction,purescriptOperatorType
 syn keyword purescriptForall forall
 syn match purescriptForall "∀"
 
 " Keywords
 syn keyword purescriptConditional if then else
-syn keyword purescriptStatement do case of let in
+syn keyword purescriptStatement do case of in
+syn keyword purescriptLet let
 syn keyword purescriptWhere where
 syn match purescriptStructure "\<\(data\|newtype\|type\|class\|kind\)\>"
   \ nextgroup=purescriptType skipwhite
@@ -166,6 +177,7 @@ highlight def link purescriptBlockComment purescriptComment
 highlight def link purescriptStructure purescriptKeyword
 highlight def link purescriptKeyword Keyword
 highlight def link purescriptStatement Statement
+highlight def link purescriptLet Statement
 highlight def link purescriptOperator Operator
 highlight def link purescriptFunction Function
 highlight def link purescriptType Type