Created
June 5, 2015 04:36
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if-let-all clojure macro
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(defmacro if-let-all | |
"if-let-all evaluates every local binding sequentially and evaluates true-case only if every local binding is a truthy value. | |
true-case has access to all local bindings, but false-case doesn't have access to local bindings." | |
[bindings true-case false-case] | |
(let [pairs (partition 2 bindings) | |
names (mapv first pairs) | |
exprs (map second pairs) | |
exprs-in-if-let (fn self [[name1 & more-names] [expr1 & more-exprs]] | |
`(if-let [~name1 ~expr1] | |
~(if more-names | |
(self more-names more-exprs) | |
names))) | |
things (exprs-in-if-let names exprs)] | |
`(if-let [~names ~things] | |
~true-case | |
~false-case))) |
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