YOW WEST 2014: "Adopting Functional Programming Languages"

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LANGUAGES

ADOPTINGPROGRAMMINGFUNCTIONAL

Andy Marks @andee_marks amarks@thoughtworks.com

ADOPTING FUNCTIONAL

PROGRAMMING LANGUAGES

(reduce + (map #(/ 1.0 % %) (range 1 1001)))

lists:sum([1/math:pow(X,2) || X <- lists:seq(1,1000)]).

sum [1 / x ^ 2 | x <- [1..1000]]

1 to 1000 map (x => 1.0 / (x * x)) sum

let rec sum n = if n < 1 then 0.0 else sum (n-1) +. 1.0 /. float (n*n) in sum 1000

!

Computation via functional evaluation Higher order functions

Immutability

Source: http://rosettacode.org/wiki/Sum_of_a_series

1996 2013

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LANGUAGES

ADOPTINGPROGRAMMINGFUNCTIONAL

10 BUTSA TALE OF

BUT… IT’S JUST FOR ACADEMICS

#1

5

6

+ FP =

+ FP =

+ FP =

BUT… NO ONE ELSE IS USING THEM

#2

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8

BUT… THEY’RE JUST THE SHINY NEW TOY

#3

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10

BUT… THEY’RE TOO NICHE FOR GENERAL USE

#4

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HTTP ✅

Test automation ✅

Database IO ✅

Build automation ✅

etc ✅

BUT… I DON’T “GET” MONADS

#5

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BUT… I’M ADDICTED TO MUTABLE STATE

#6

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BUT… I ALREADY HAVE CLOSURES IN C#.

#7

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BUT… THE TOOLS ARE TOO IMMATURE

#8

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BUT… THERE ARE NO DEVELOPERS WHO KNOW SCALA

#9

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BUT… I DON’T WANT TO LEARN ANOTHER SYNTAX

#10

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CONCLUSION

Distribution + concurrency Data + data analysis Lower barrier to entry Hybrid languages

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LANGUAGES

ADOPTINGPROGRAMMINGFUNCTIONAL

Andy Marks @andee_marks amarks@thoughtworks.com

THANKS!