First crack at implementing some syntax

ftdetect/kokafiletype.vim

@@ -0,0 +1 @@
+au BufNewfile,BufEnter *.kk setf koka

syntax/koka.vim

@@ -5,3 +5,31 @@
 if exists("b:current_syntax")
     finish
 endif
+
+" Keywords
+syn keyword KokaKeyword infix infixr infixl prefix type struct alias con forall exists some fn val var
+            \ extern if then else elif match return with in handle handler mask override control rcontrol
+            \ effect named module import as public private abstract pub interface yield qualified hiding unsafe
+
+highlight def link KokaKeyword Keyword
+
+" Functions
+syn keyword KokaKeyword fun nextgroup=KokaFunName skipwhite skipempty
+syn match KokaFunName /\v[a-z][A-Za-z0-9\-_]*/ display contained
+highlight def link KokaFunName Function
+
+
+" Core Types
+syn keyword KokaCoreType any bool cfield char ctail double ediv either float32 global hdiv int int32
+            \ int64 local-var maybe optional order ref reuse ssize_t string uint8 vector void
+highlight def link KokaCoreType Type
+
+" Comments
+syn region KokaLineComment start="//" end="$"
+syn region KokaBlockComment matchgroup=KokaBlockComment start="/\*\%(!\|\*[*/]\@!\)\@!" end="\*/" contains=KokaBlockCommentNested
+syn region KokaBlockCommentNested matchgroup=KokaBlockComment start="/\*" end="\*/" contains=KokaBlockCommentNested
+
+highlight def link KokaLineComment Comment
+highlight def link KokaBlockComment Comment
+highlight def link KokaBlockCommentNested Comment
+