What does the @ (at sign) mean in Clojure?

clojure, datomic

Solution

This is the deref macro character. What you're looking for in the context of Datomic is at:

http://docs.datomic.com/transactions.html

under Processing Transactions:

In Clojure, you can also use the deref method or @ to get a transaction's result.

For more on deref in Clojure, see:

http://clojuredocs.org/clojure_core/clojure.core/deref

Problem

I found this line of Clojure code: `@(d/transact conn schema-tx)`. It's a Datomic statement that creates a database schema. I couldn't find anything relevant on Google due to difficulties searching for characters like "@". What does the 'at' sign mean before the first parenthesis?

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