anchor.diff:  assert mixin == commandLine.getMixins().get("myMixin");
   assert mixin.verbosity.length == 3;
   ----
  -
  -==== `@Mixin` Annotation
  -A command can also include a mixin by annotating a field with `@Mixin`. All picocli annotations found in the mixin class
  -are added to the command that has a field annotated with `@Mixin`. For example, again using the sample `ReusableOptions` class <<Reuse,defined above>>:
  -
  -[source,java]
  -----
  -@Command(name = "zip", description = "Example reuse with @Mixin annotation.")
  -public class MyCommand {
  -
  -    // adds the options defined in ReusableOptions to this command
  -    @Mixin
  -    private ReusableOptions myMixin;
  -    ...
  -}
  -----
  -In addition to adding the options, subcommands and command attributes of the mixed-in object to the command,
  -the mixed-in object is also injected into the field annotated with `@Mixin`, making it trivial for the command to reference the mixed-in object if necessary.
  -
  -[source,java]
  -----
  -MyCommand zip = new MyCommand();
  -CommandLine commandLine = new CommandLine(zip);
  -commandLine.parseArgs("-vvv");
  -
  -// the options defined in ReusableOptions have been added to the zip command
  -assert zip.myMixin.verbosity.length == 3;
  -----
  -
  -Mixins added with the `@Mixin` annotation can also be accessed via the map returned by `CommandLine.getMixins`.
  -
  -The GitHub project has a https://github.com/remkop/picocli/tree/master/picocli-examples/src/main/java/picocli/examples/mixin[full working example].
   
   
   === Use Case: Sharing Options
  
positive.code: You may find yourself defining the same options, parameters or command attributes in many command line applications.
  To reduce duplication, picocli supports both subclassing and mixins as ways to reuse such options and attributes.
  
  For both mechanisms, the first step is to extract these options, parameters and command attributes into a separate class. Below is an example class, `ReusableOptions`, that we will use in example scenarios in this chapter:
  
  [source,java]
  ----
  
negative.code:     protected boolean[] verbosity = new boolean[0];
  }
  ----
  
  Now, any command defined in a class that extends `ReusableOptions` will inherit the `--verbose` option, and generate a usage help message in the same spacious style. Example code:
  
  [source,java]
  ----
  