.dig not allowing to make connections

[marado]

.h dig
Command : dig
Usage   : .dig <direction> <name>

.dig <direction> <name> will create a new place next to here, called <name>, in
<direction>'s direction. If that place already exists, but a passage doesn't,
just create the passage. More info about directions in .file directions.

Level   : Adult or greater.
.dig SE G
:: You're trying to create a place called G where there's already
another place called G! Maybe you want to .destroy that
one first, or recheck your .map and make sure of what you're trying to
do?

Instead of complaining that there's another place there (at least when the name of the place is the same), warn that the place already exists so we'll only make a connection... but make it!