What could a Clojure editor be like? 

Char editor (Notepad, DOS E) 

Char editor (Notepad, DOS E) Text editor (vi, emacs, ed) 

Char editor (Notepad, DOS E) Text editor (vi, emacs, ed) Code editor (emacs, acme, vs code, sublime) 

Char editor (Notepad, DOS E) Text editor (vi, emacs, ed) Code editor (emacs, acme, vs code, sublime) Code editor + dev. env. (IDE) (emacs, vs code, atom, IDEA, Eclipse, Xcode, etc) 

Char editor (Notepad, DOS E) Text editor (vi, emacs, ed) Code editor (emacs, acme, vs code, sublime) Code editor + dev. env. (IDE) (emacs, vs code, atom, IDEA, Eclipse, Xcode, etc) Visual programming (Node-RED, Scratch, Modkit, Blocky) 

Scratch 

Google's Blocky 

Node-RED 

Luna 

Unreal Engine 4 "Blueprints" 

Feynman Diagram 

• Immediate feedback • Composition • Data flow • Encourages FP • Reducing accidental complexity Benefits of a visual approach 

• Immediate feedback → REPL • Composition → Higher order functions, natural composability • Data flow → it's just data!™ • Encourages FP → duh! • Reducing accidental complexity → we still have lots In the context of LISP/Clojure 

• Function promotion
 !#(bla %) → (fn [a] (bla a)) → (defn real-foo [a] (bla a)) • if → cond • wrap in let, promote let • Namespaces, import • Refactoring • Simple: rename, replace function, change order • Complex: change flow, change data structure IDE level complexity Char editor (Notepad, DOS E) Text editor (vi, emacs, ed) Code editor (emacs, acme, vs code, sublime) Code editor + dev. env. (IDE) (emac/cider, IDEA/Cursive, Eclipse, Xcode, etc) 

• Not flexible enough • Not expressive enough • Either too simple or too niche • Mouse! Cons of a visual approach 

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• "Inventing on principle", Brett Victor • "Inspiring a future Clojure editor with forgotten Lisp UX", Shaun Lebron • ProtoREPL Check out