Update runtime files
diff --git a/runtime/syntax/vim.vim b/runtime/syntax/vim.vim
index c080a26..e0096f6 100644
--- a/runtime/syntax/vim.vim
+++ b/runtime/syntax/vim.vim
@@ -379,7 +379,8 @@
" Let: {{{2
" ===
syn keyword vimLet let unl[et] skipwhite nextgroup=vimVar,vimFuncVar,vimLetHereDoc
-VimFoldh syn region vimLetHereDoc matchgroup=vimLetHereDocStart start='=<<\s\+\%(trim\>\)\=\s*\z(\h\w*\)' matchgroup=vimLetHereDocStop end='^\s*\z1\s*$' contains=vimComment
+VimFoldh syn region vimLetHereDoc matchgroup=vimLetHereDocStart start='=<<\s\+\%(trim\>\)\=\s*\z([^a-z]\S*\)' matchgroup=vimLetHereDocStop end='^\s*\z1\s*$' contains=vimComment
+syn cluster vimFuncBodyList add=vimLetHereDoc
" Abbreviations: {{{2
" =============