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+Interfaces in ARF are like interfaces in Go, that is to say, their methods are
+defined and any object that has at least those methods can fulfill that
+interface.
+
+They are defined like this:
+
+```
+face ro ReadWriter
+	read
+		> into:{Byte ..}
+		< amountRead:Size
+	write
+		> buffer{Byte ..}
+		< amountWrote:Size
+```
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