code: public ConjunctionMatcher<T> and(Matcher<? super T> matcher)
  	{
  		requireNonNull(matcher, "matcher");
  		
  		return new ConjunctionMatcher<>(compositeDescription, concat(matchers, matcher));
  	}
docs: Returns a composite matcher that comprises of this matcher logically ANDed with the specified matcher.
  <p>
  Note that this method returns a new matcher and does not modify this instance.
  
  @param matcher
  the matcher to logically AND to this matcher
  @return the composed matcher