Olsen - Getting clojure: build your functional skills one idea at a time

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To

Mikey

Felicia

Jackson

Charlie & Jennifer

Tim & Emily & Evan

Nicholas & Jonathan

Meg & Alex & Zachary

and

Scott Downie

The future is in your hands.

If it takes a village to raise a child, it takes a community to build aprogramming language. Id like to thank Rich Hickey for creating Clojure andeveryone who has ever contributed even a little to Clojure for making myprofessional life just a bit better.

Id also like to offer my warm thanks to everyone at Cognitect, especiallyJustin Gehtland and Mike Nygard for their generous support of this book.

In the same spirit, while authors get most of the credit,behind every book stands a village of people who contributedin some way. So Id like to say thanks to JamieKite, Alex Miller, Ben Vandgrift, Nola Stowe, and Karen Cross for sufferingthrough the early drafts of this book and suggesting ways that I could turn aconfused mess into something people might read.

Special thanks to Jay Martin for his insightful commentsand toPaul deGrandis for pointing out the MAL project.

Im grateful to Jeb Beich for his patience with my amazingly stupid questions.

Id also like to thankScott Downie,Jackson Olsen,Alex Redington,Tibor Simic,Nola Stowe,Stefan Turalski,and Ben Vandgriftfor providing technical feedback as this book went to press.

Im also grateful to all the folks at The Pragmatic Bookshelf (especiallyMichael Swaine) for their help in pushing this bookout the door.

Last and certainly not least Id like to thank my lifelong partnerKaren Cross for her constant love and support and encouragement.And thanks to my son Jackson Olsen for the same and for forgivingme for making fun of The Wheel of Time . Well, mostly forgiving me.

I have been writing this bookat least in my headfor decades.As a professional programmer who has used everything from assembly language andFORTRAN to C and Python and Java and Ruby, Ive spentmuch of my career longing to get myhands on a better programming language. In my minds eye I could see exactlywhat I wanted: I wanted a language that had the stripped-down syntax of Lisp.I wanted a language that embraced the power of functional programming. I wanteda language that was fast enough to run the real-world applications that I waswriting.Most of all I wanted a language that had all the above and ranon the computing platforms I worked with.For years my imaginary programming language remained just thatimaginary.I spent a lot of that time mentally composing a book that wouldlay out the case for my dream programming language.