anchor.diff:  The `CommandLine` class offers two methods that allow external components to detect whether
   usage help or version information was requested (without inspecting the annotated domain object):
   
  -* `CommandLine.isUsageHelpRequested()` returns `true` if the parser matched an option annotated with `usageHelp=true`
  -* `CommandLine.isVersionHelpRequested()` returns `true` if the parser matched an option annotated with `versionHelp=true`
  +* `CommandLine::isUsageHelpRequested` returns `true` if the parser matched an option annotated with `usageHelp=true`
  +* `CommandLine::isVersionHelpRequested` returns `true` if the parser matched an option annotated with `versionHelp=true`
   
   [source,java]
   ----
  
positive.code: The next argument `-a` is recognized and processed as a known option like you would expect.
  
  === Stop At Unmatched
  From picocli 2.3, applications can call `CommandLine.setStopAtUnmatched(true)` to force the parser to stop interpreting
  options and positional parameters as soon as it encounters an unmatched argument.
  
  When this flag is set, the first unmatched argument and all subsequent command line arguments are added to the
  unmatched arguments list returned by `CommandLine.getUnmatchedArguments()`.
  
  === Toggle Boolean Flags
  When a flag option is specified on the command line picocli will set its value to the opposite of its _default_ value.
  
negative.code: }
  AbbreviationsAndPosix app = new AbbreviationsAndPosix();
  new CommandLine(app).setAbbreviatedOptionsAllowed(true).parseArgs("-AB");
  assertTrue(app.aaaBbb); // the long option is matched from abbreviated input -AB
  assertFalse(app.a);
  assertFalse(app.b);
  ----
  