fix: highlight & in identifier as error

CHANGELOG.md

@@ -9,6 +9,10 @@
   - `\u{..}` is supported by Lua>=5.3, highlighted as error otherwise.
 - Support `accumulate` macro.
 
+### Fixed
+
+- `&` in identifier is now highlighted as error (Fennel 1.0.0).
+
 ## [0.2][v0.2] (2021-06-20)
 
 ### Added

syntax/fennel.vim

@@ -46,12 +46,12 @@ syn keyword fennelConstant nil
 " Identifier, symbol, and keyword {{{2
 "
 " <identifier> -> <initial> <subsequent> *
-" where <initial> -> [^#:0-9[:space:]\n"'(),;@\[\]\\`{}~]
-"       <subsequent> ->   [^[:space:]\n"'(),;@\[\]\\`{}~]
-syn match fennelIdentifier /[^#:0-9[:space:]\n"'(),;@\[\]\\`{}~][^[:space:]\n"'(),;@\[\]\\`{}~]*/
+" where <initial> -> [^#&:0-9[:space:]\n"'(),;@\[\]\\`{}~]
+"       <subsequent> ->   [^&[:space:]\n"'(),;@\[\]\\`{}~]
+syn match fennelIdentifier /[^#&:0-9[:space:]\n"'(),;@\[\]\\`{}~][^&[:space:]\n"'(),;@\[\]\\`{}~]*/
 syn match fennelLuaTableItemAccessor /\./ contained containedin=fennelIdentifier
 syn match fennelLuaMethodCall /:/ contained containedin=fennelIdentifier
-syn match fennelSymbol /[^#:0-9[:space:]\n"'(),;@\[\]\\`{}~][^[:space:]\n"'(),;@\[\]\\`{}~]*/ contained
+syn match fennelSymbol /[^#&:0-9[:space:]\n"'(),;@\[\]\\`{}~][^&[:space:]\n"'(),;@\[\]\\`{}~]*/ contained
 " <keyword> -> : <subsequent> +
 " Keyword such as ::: is accepted by Fennel! 
 syn match fennelKeyword /:[^[:space:]\n"'(),;@\[\]\\`{}~]\+/