let files = filter(globpath(&rtp, 'syntax/basic/function.vim', 1, 1), { _, v -> v !~ "vim-polyglot" && v !~ $VIMRUNTIME && v !~ "after" })
if len(files) > 0
exec 'source ' . files[0]
finish
endif
if !exists('g:polyglot_disabled') || index(g:polyglot_disabled, 'typescript') == -1
syntax keyword typescriptAsyncFuncKeyword async
\ nextgroup=typescriptFuncKeyword,typescriptArrowFuncDef
\ skipwhite
syntax keyword typescriptAsyncFuncKeyword await
\ nextgroup=@typescriptValue
\ skipwhite
syntax keyword typescriptFuncKeyword function
\ nextgroup=typescriptAsyncFunc,typescriptFuncName,@typescriptCallSignature
\ skipwhite skipempty
syntax match typescriptAsyncFunc contained /*/
\ nextgroup=typescriptFuncName,@typescriptCallSignature
\ skipwhite skipempty
syntax match typescriptFuncName contained /\K\k*/
\ nextgroup=@typescriptCallSignature
\ skipwhite
" destructuring ({ a: ee }) =>
syntax match typescriptArrowFuncDef contained /(\(\s*\({\_[^}]*}\|\k\+\)\(:\_[^)]\)\?,\?\)\+)\s*=>/
\ contains=typescriptArrowFuncArg,typescriptArrowFunc
\ nextgroup=@typescriptExpression,typescriptBlock
\ skipwhite skipempty
" matches `(a) =>` or `([a]) =>` or
" `(
" a) =>`
syntax match typescriptArrowFuncDef contained /(\(\_s*[a-zA-Z\$_\[.]\_[^)]*\)*)\s*=>/
\ contains=typescriptArrowFuncArg,typescriptArrowFunc
\ nextgroup=@typescriptExpression,typescriptBlock
\ skipwhite skipempty
syntax match typescriptArrowFuncDef contained /\K\k*\s*=>/
\ contains=typescriptArrowFuncArg,typescriptArrowFunc
\ nextgroup=@typescriptExpression,typescriptBlock
\ skipwhite skipempty
" TODO: optimize this pattern
syntax region typescriptArrowFuncDef contained start=/(\_[^(^)]*):/ end=/=>/
\ contains=typescriptArrowFuncArg,typescriptArrowFunc,typescriptTypeAnnotation
\ nextgroup=@typescriptExpression,typescriptBlock
\ skipwhite skipempty keepend
syntax match typescriptArrowFunc /=>/
syntax match typescriptArrowFuncArg contained /\K\k*/
syntax region typescriptArrowFuncArg contained start=/<\|(/ end=/\ze=>/ contains=@typescriptCallSignature
syntax region typescriptReturnAnnotation contained start=/:/ end=/{/me=e-1 contains=@typescriptType nextgroup=typescriptBlock
syntax region typescriptFuncImpl contained start=/function\>/ end=/{/me=e-1
\ contains=typescriptFuncKeyword
\ nextgroup=typescriptBlock
syntax cluster typescriptCallImpl contains=typescriptGenericImpl,typescriptParamImpl
syntax region typescriptGenericImpl matchgroup=typescriptTypeBrackets
\ start=/</ end=/>/ skip=/\s*,\s*/
\ contains=typescriptTypeParameter
\ nextgroup=typescriptParamImpl
\ contained skipwhite
syntax region typescriptParamImpl matchgroup=typescriptParens
\ start=/(/ end=/)/
\ contains=typescriptDecorator,@typescriptParameterList,@typescriptComments
\ nextgroup=typescriptReturnAnnotation,typescriptBlock
\ contained skipwhite skipnl
endif
