jbgreer

jbgreer

Programming Clojure, Fourth Edition:confusing seq on map examples

I cannot reference a page number as I’m reading digital edition, Version P1.0 (May 2026), but in the “Everything is Seq-able” section of Chapter 4 the text includes examples of the use of first and rest functions on maps:

(first {:fname ​"Aaron"​ :lname ​"Bedra"​}) 
-> [:lname ​"Bedra"​] 

(rest {:fname ​"Aaron"​ :lname ​"Bedra"​})
→ ([:fname ​"Aaron"​])

While standard maps do not guarantee a specific ordering of the keys, I admit I’m uncertain as to whether that is the cause of the counterintuitive results. I believe beginning Clojurians would be better served by swapping the resulting values in the examples.

Thanks for an excellent book.

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