F# So Far

A few tidbits about our experience building our first couple subsystems in F#.

Transcript

1. Our Experience
   So far
   With
   F#
   Matt & Jake
   

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2. What We’re Building
   - Prism global nav BC
   - ~8 listeners
   - 1 publisher
   - 1 api
   

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3. Why F# for us?
   - Like functional programming, want more
   - .Net ecosystem & expertise
   - Appeal of F# when coming to .Net
   - Strong types
   

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4. The Language
   - Syntax is different than most imperative
   - Took days to grok basic syntax
   - Felt productive w/in a few weeks
   - Can use all of .Net framework
   - Interop sometimes awkward
   - TDD is great
   - Light stubs, no explicit interfaces
   

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5. Deployment
   - Pre-existing Windows servers
   - server-farm for listeners
   - internal-tools for api
   - Templates exist for TeamCity
   - Operationally equivalent w/ all other .Net
   warez
   

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6. Shared Libs
   - Can use all PS .Net libraries
   - messaging
   - logging
   - settings
   - postgres
   

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7. Abstractions
   - Mostly just functions
   - Didn’t use classes except for interop
   - No IoC container
   

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8. Tooling
   - Visual Studio
   - F# Power Tools are great
   - Rename, import, navigate to
   - ReSharper mostly absent
   - Weak refactorings
   - F# dotnetcore is not ready for prod
   

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9. Dynamic Data
   - www.youneedlotsoftypes.com
   - Painful in test
   - Partial stubs
   - Incomplete request bodies
   - Duck typing supposedly possible
   

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10. Type Inference
    - Nice to not have to write out all types
    - Sometimes inference gets confused
    - Have to annotate
    - Later can remove
    

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11. Code Organization
    - Modules group functions
    - Trying different ways to organize types
    - Forward-only compiler
    - Still getting better
    

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12. Quirfuffles
    - Just go add an assemblyRedirect
    - Just recompile src to make ur tests happy
    - Just restart Visual Studio
    

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13. Learning
    - Some strong resources
    - fsharpforfunandprofit.com
    - Pluralsight vids \m/
    - Good Google hits
    - Still growing in our proficiency
    - Language still has untapped potential
    

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14. Who might like F#?
    Likes FP and…
    - .Net - ops equivalent, all libs
    - Strong types - no wild dynamic code, sum
    types
    - Safety - immutability by default, total functions
    - Type inference - modern convenience
    - Expressive functional constructs - pipes,
    function composition, auto curry, pattern matching
    

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15. What now?
    - Finish Prism BC
    - Determine if there’s enough org interest to
    support this and future F# projects
    - Move F# from “investigate” to “avoid” or
    “adopt”
    - Profit
    

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16. IGHT!
    Thank you
    

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