method1(o) => switch (o) {
final int a => 'working',
final String a => 'working',
final () a => 'working',
final (int, String) a => 'working',
final int a? => 'working',
final String a? => 'working',
final () a? => 'working',
final (int, String) a? => 'working',
(:final () a) => 'working',
(:final (int, String) a) => 'working',
(:final int a?) => 'working',
(:final String a?) => 'working',
(:final () a?) => 'working',
(:final (int, String) a?) => 'working',
_ => '',
};

method2(o) => switch (o) {
final int async => 'working',
final String async => 'working',

final () async => 'working',
final (int, String) async => 'working',
final int async? => 'working',
final String async? => 'working',
final () async? => 'working',
final (int, String) async? => 'working',
(:final () async) => 'working',
(:final (int, String) async) => 'working',
(:final int async?) => 'working',
(:final String async?) => 'working',
(:final () async?) => 'working',
(:final (int, String) async?) => 'working',
_ => '',
};

void foo() {

() async => print("async unnamed taking 0 parameters");
(int x) async => print("async unnamed taking 1 parameter");
(int x, int y) async => print("async unnamed taking 2 parameters");
}

method1[StringToken]([BeginToken]o[StringToken])[SimpleToken] =>[SimpleToken] switch[KeywordToken] ([BeginToken]o[StringToken])[SimpleToken] {[BeginToken]
final[KeywordToken] int[StringToken] a[StringToken] =>[SimpleToken] 'working'[StringToken],[SimpleToken]
final[KeywordToken] String[StringToken] a[StringToken] =>[SimpleToken] 'working'[StringToken],[SimpleToken]
final[KeywordToken] ([BeginToken])[SimpleToken] a[StringToken] =>[SimpleToken] 'working'[StringToken],[SimpleToken]
final[KeywordToken] ([BeginToken]int[StringToken],[SimpleToken] String[StringToken])[SimpleToken] a[StringToken] =>[SimpleToken] 'working'[StringToken],[SimpleToken]
final[KeywordToken] int[StringToken] a[StringToken]?[SimpleToken] =>[SimpleToken] 'working'[StringToken],[SimpleToken]
final[KeywordToken] String[StringToken] a[StringToken]?[SimpleToken] =>[SimpleToken] 'working'[StringToken],[SimpleToken]
final[KeywordToken] ([BeginToken])[SimpleToken] a[StringToken]?[SimpleToken] =>[SimpleToken] 'working'[StringToken],[SimpleToken]
final[KeywordToken] ([BeginToken]int[StringToken],[SimpleToken] String[StringToken])[SimpleToken] a[StringToken]?[SimpleToken] =>[SimpleToken] 'working'[StringToken],[SimpleToken]
([BeginToken]:[SimpleToken]final[KeywordToken] ([BeginToken])[SimpleToken] a[StringToken])[SimpleToken] =>[SimpleToken] 'working'[StringToken],[SimpleToken]
([BeginToken]:[SimpleToken]final[KeywordToken] ([BeginToken]int[StringToken],[SimpleToken] String[StringToken])[SimpleToken] a[StringToken])[SimpleToken] =>[SimpleToken] 'working'[StringToken],[SimpleToken]
([BeginToken]:[SimpleToken]final[KeywordToken] int[StringToken] a[StringToken]?[SimpleToken])[SimpleToken] =>[SimpleToken] 'working'[StringToken],[SimpleToken]
([BeginToken]:[SimpleToken]final[KeywordToken] String[StringToken] a[StringToken]?[SimpleToken])[SimpleToken] =>[SimpleToken] 'working'[StringToken],[SimpleToken]
([BeginToken]:[SimpleToken]final[KeywordToken] ([BeginToken])[SimpleToken] a[StringToken]?[SimpleToken])[SimpleToken] =>[SimpleToken] 'working'[StringToken],[SimpleToken]
([BeginToken]:[SimpleToken]final[KeywordToken] ([BeginToken]int[StringToken],[SimpleToken] String[StringToken])[SimpleToken] a[StringToken]?[SimpleToken])[SimpleToken] =>[SimpleToken] 'working'[StringToken],[SimpleToken]
_[StringToken] =>[SimpleToken] ''[StringToken],[SimpleToken]
}[SimpleToken];[SimpleToken]

method2[StringToken]([BeginToken]o[StringToken])[SimpleToken] =>[SimpleToken] switch[KeywordToken] ([BeginToken]o[StringToken])[SimpleToken] {[BeginToken]
final[KeywordToken] int[StringToken] async[KeywordToken] =>[SimpleToken] 'working'[StringToken],[SimpleToken]
final[KeywordToken] String[StringToken] async[KeywordToken] =>[SimpleToken] 'working'[StringToken],[SimpleToken]

final[KeywordToken] ([BeginToken])[SimpleToken] async[KeywordToken] =>[SimpleToken] 'working'[StringToken],[SimpleToken]
final[KeywordToken] ([BeginToken]int[StringToken],[SimpleToken] String[StringToken])[SimpleToken] async[KeywordToken] =>[SimpleToken] 'working'[StringToken],[SimpleToken]
final[KeywordToken] int[StringToken] async[KeywordToken]?[SimpleToken] =>[SimpleToken] 'working'[StringToken],[SimpleToken]
final[KeywordToken] String[StringToken] async[KeywordToken]?[SimpleToken] =>[SimpleToken] 'working'[StringToken],[SimpleToken]
final[KeywordToken] ([BeginToken])[SimpleToken] async[KeywordToken]?[SimpleToken] =>[SimpleToken] 'working'[StringToken],[SimpleToken]
final[KeywordToken] ([BeginToken]int[StringToken],[SimpleToken] String[StringToken])[SimpleToken] async[KeywordToken]?[SimpleToken] =>[SimpleToken] 'working'[StringToken],[SimpleToken]
([BeginToken]:[SimpleToken]final[KeywordToken] ([BeginToken])[SimpleToken] async[KeywordToken])[SimpleToken] =>[SimpleToken] 'working'[StringToken],[SimpleToken]
([BeginToken]:[SimpleToken]final[KeywordToken] ([BeginToken]int[StringToken],[SimpleToken] String[StringToken])[SimpleToken] async[KeywordToken])[SimpleToken] =>[SimpleToken] 'working'[StringToken],[SimpleToken]
([BeginToken]:[SimpleToken]final[KeywordToken] int[StringToken] async[KeywordToken]?[SimpleToken])[SimpleToken] =>[SimpleToken] 'working'[StringToken],[SimpleToken]
([BeginToken]:[SimpleToken]final[KeywordToken] String[StringToken] async[KeywordToken]?[SimpleToken])[SimpleToken] =>[SimpleToken] 'working'[StringToken],[SimpleToken]
([BeginToken]:[SimpleToken]final[KeywordToken] ([BeginToken])[SimpleToken] async[KeywordToken]?[SimpleToken])[SimpleToken] =>[SimpleToken] 'working'[StringToken],[SimpleToken]
([BeginToken]:[SimpleToken]final[KeywordToken] ([BeginToken]int[StringToken],[SimpleToken] String[StringToken])[SimpleToken] async[KeywordToken]?[SimpleToken])[SimpleToken] =>[SimpleToken] 'working'[StringToken],[SimpleToken]
_[StringToken] =>[SimpleToken] ''[StringToken],[SimpleToken]
}[SimpleToken];[SimpleToken]

void[KeywordToken] foo[StringToken]([BeginToken])[SimpleToken] {[BeginToken]

([BeginToken])[SimpleToken] async[KeywordToken] =>[SimpleToken] print[StringToken]([BeginToken]"async unnamed taking 0 parameters"[StringToken])[SimpleToken];[SimpleToken]
([BeginToken]int[StringToken] x[StringToken])[SimpleToken] async[KeywordToken] =>[SimpleToken] print[StringToken]([BeginToken]"async unnamed taking 1 parameter"[StringToken])[SimpleToken];[SimpleToken]
([BeginToken]int[StringToken] x[StringToken],[SimpleToken] int[StringToken] y[StringToken])[SimpleToken] async[KeywordToken] =>[SimpleToken] print[StringToken]([BeginToken]"async unnamed taking 2 parameters"[StringToken])[SimpleToken];[SimpleToken]
}[SimpleToken][SimpleToken]