Yes, it's now easy to mix custom sieve code with rules. And the standard rules are much more powerful, so custom sieve is not needed as often. For example, when reading a message you can use the
More>Add rule from message feature to immediately create a new rule based on any message. This is an amazing feature, and I'm trying to remember to use it more often.
The recent improvements to the Fastmail sieve support allows a user to implement many features which were not previously available. For example, adding a date range to the vacation feature results in code similar to:
Code:
if
allof(
currentdate :zone "+0000" :value "ge" "iso8601" "2017-04-13T05:00:00Z",
currentdate :zone "+0000" :value "le" "iso8601" "2017-04-30T05:00:00Z"
)
{
... sieve ...
}
So you can add sieve code which affects how your rules are processed on different dates (and times). For example, you could automatically forward certain messages (or send a vacation style reply) only on weekdays after working hours and on weekends.
For details on the improvements, see this post:
Improvements to both sieve language support and rules system
Bill