Add a command line parsing procedure

source/Lexer.def

@@ -2,6 +2,8 @@ DEFINITION MODULE Lexer;
 
 FROM FIO IMPORT File;
 
+FROM Common IMPORT Identifier;
+
 TYPE
   PLexerBuffer = POINTER TO CHAR;
   Lexer = RECORD
@@ -81,7 +83,8 @@ TYPE
   LexerToken = RECORD
     CASE kind: LexerKind OF
       lexerKindBoolean: booleanKind: BOOLEAN |
-      lexerKindIdentifier: identifierKind: ARRAY[1..256] OF CHAR
+      lexerKindIdentifier: identifierKind: Identifier |
+      lexerKindInteger: integerKind: INTEGER
     END
   END;
   PLexerToken = POINTER TO LexerToken;