Allowed underscore (_) to be used in identifiers.

Author: KOLANICH

Coco/Scanner.py

@@ -185,7 +185,7 @@ def scan2(self, buf: str) -> str:
 
 	def scan3(self, state: int, apx: int, buf: str) -> typing.Tuple[typing.Optional[int], ScannerEnum, int, str]:
 		if state == 20:
-			if "0" <= self.ch <= "9" or "A" <= self.ch <= "Z" or "a" <= self.ch <= "z":
+			if "0" <= self.ch <= "9" or "A" <= self.ch <= "Z" or self.ch == "_" or "a" <= self.ch <= "z":
 				buf += str(self.ch)
 				self.NextCh()
 				return 20, self.t.kind, apx, buf
@@ -199,7 +199,7 @@ def scan3(self, state: int, apx: int, buf: str) -> typing.Tuple[typing.Optional[
 				return 21, self.t.kind, apx, buf
 			return None, self.__class__.ENUM.number_Sym, apx, buf
 		if state == 22:
-			if "0" <= self.ch <= "9" or "A" <= self.ch <= "Z" or "a" <= self.ch <= "z":
+			if "0" <= self.ch <= "9" or "A" <= self.ch <= "Z" or self.ch == "_" or "a" <= self.ch <= "z":
 				buf += str(self.ch)
 				self.NextCh()
 				return 22, self.t.kind, apx, buf

sources/Coco.atg

@@ -49,7 +49,7 @@ COMPILER Coco
 #-------------------------------------------------------------------------
 
 CHARACTERS
-	letter	= "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz".
+	letter	= "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz_".
 	digit		= "0123456789".
 	cr		= '\r'.
 	lf		= '\n'.