Keith Harrison

Why Hymans Use F#

Risk ModellingActuarial Consultancy

Port Legacy System

Familiar

Composable

Pragmatic

Familiar

public class Multiplier { public int Factor;

public int Calculate(int value) { return value * Factor; }}

var tenMultiplier = new Multiplier { Factor = 10 };var result = tenMultiplier.Calculate(2);

let createMultiplier (factor) = fun x -> x * factor let multiplyByTen = createMultiplier(10)

let result = multiplyByTen(2)

Composable

let filter people = let results = new List<Person>() for person in people do if person.Age > 30 then results.Add(person) results

let filter people age = let results = new List<Person>() for person in people do if person.Age > age then results.Add(person) results

let filter people = let results = new List<Person>() for person in people do if person.Sex = Sex.Male then results.Add(person) results

let filter filterFunction people = let results = new List<Person>() for person in people do if filterFunction() then results.Add(person) results

let filter filterFunction people = let results = new List<Person>() for person in people do if filterFunction() then results.Add(person) results

filter (fun p -> p.Age > 30) personListfilter (fun p -> p.Age > 40) personListfilter (fun p -> p.Sex = Sex.Male) personList

let isOver30 p = p.Age > 30let isOver40 p = p.Age > 40let isMale p = p.Sex = Sex.Male

filter isOver30 personListfilter isOver40 personListfilter isMale personList

filter isOver30 personList

personList |> filter isOver30

personList |> filter isOver30 |> filter isMale

Pragmatic

F#

Functional Imperative Object Oriented

Familiar

Composable

Pragmatic

Books

We’re Hiring

• www.hymans.co.uk/contact-us.aspx• http://careers.stackoverflow.com/uk/company/hymans-robertson

• keith.Harrison@hymans.co.uk• @KeithDHar• http://www.linkedin.com/in/keithdharrison

Questions?