[tlaplus] Re: Function sets with distinct mappings

[Andrew Helwer <andrew.helwer@xxxxxxxxx>]

UserSenderSet == { f \in [Users -> Users] : \A u \in Users : f[u] /= u }

On Sunday, February 27, 2022 at 5:32:27 PM UTC-5 thomas...@xxxxxxxxx wrote:

I am trying to make a set of functions of mappings of sender->receiver: 

Users == {"jack", "jill", "cindy", "bobby"}

UserSenderSet == [Users -> Users]

This almost does what I want, but we have many functions where sender->receiver are the same person, which is not what I want:

[jack |-> "jack", jill |-> "jack", cindy |-> "jack", bobby |-> "jack"]

How do I go about filtering down to set of functions that don't contain mappings of to themselves?

-- 
You received this message because you are subscribed to the Google Groups "tlaplus" group.
To unsubscribe from this group and stop receiving emails from it, send an email to tlaplus+unsubscribe@xxxxxxxxxxxxxxxx.
To view this discussion on the web visit https://groups.google.com/d/msgid/tlaplus/fc418c32-5fea-482c-a4ad-16d22f1068ben%40googlegroups.com.