discard;
Discard is used to silently throw away the message. It does so by simply canceling the implicit keep. If discard is used with other actions, the other actions still happen. Discard is compatible with all other actions. (For instance fileinto+discard is equivalent to fileinto.)
Discard is silent, it does not return a non-delivery notification of any kind.
In the following script, any mail from "idiot@example.edu" is thrown out.
if header :contains ["from"] ["idiot@example.edu"] {
discard;
}
Core : Requires no import statement
RFC3028