If a command contains nested merge commands, then it will not be parsed until merge time. In fact, a special MergeEngine will be created to merge the command and then it will be parsed. Finally, note that the command keywords are case insensitive. This language is both richer and extensible, however. This command is a no-op.
Nothing is inserted in the merge output.
Places the date in the merge output. This is the long form and can be used to get around problems with keys that have the same names as commands. The first parameter is a variable name to be used as an iterator. Each time through the loop, this variable will take on a new value. The final parameter is a special tag.