This template does nothing.
More exactly, it outputs the null string. It's useful for programming advanced templates.
It often is used within a template to the right of an equals sign.
It's also possible to use ((ns:0))
instead of ((void))
. Attackers could manipulate ((void))
but not (( ns:0 )), the empty/void/null string for the main namespace.
Some magic words like __END__ might also have the desired effect of doing nothing.