code: private Stmt.Break parseBreakStatement(EnclosingScope scope) {
  		int start = index;
  		// Match the break keyword
  		Token t = match(Break);
  		int end = index;
  		matchEndLine();
  		// Check that break statement makes sense at this point.
  		if (!scope.isInLoop()) {
  			syntaxError("break outside switch or loop", t);
  		}
  		// Done.
  		return annotateSourceLocation(new Stmt.Break(),start,end-1);
  	}
docs: Parse a break statement, which is of the form:
  
  <pre>
  BreakStmt ::= "break"
  </pre>
  
  @param scope
  The enclosing scope for this statement, which determines the
  set of visible (i.e. declared) variables and also the current
  indentation level.
  
  @see wyc.lang.Stmt.Break
  @return