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--- /dev/fd/13	2019-06-26 17:28:12.960405019 -0700
+++ /dev/fd/14	2019-06-26 17:28:12.960830329 -0700
@@ -70,7 +70,7 @@
 json.AAK.longitude = "173.63699340820312";
 json.AAK.name = "Buariki Airport";
 json.AAK.timezone = "10";
-json.AAK.tz_name = "\\N";
+json.AAK.tz_name = null;
 json.AAL = {};
 json.AAL.altitude = "10";

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raw_panda = "🐼"

# panda is U+1F43C according to wikipedia
puts raw_panda
puts "\uf09f\u90bc"
# puts "\u2728"
# puts "\ud83d\udc3c".force_encoding("UTF-8")

# puts raw_panda.each_codepoint { |x| p x }
# puts raw_panda.each_byte { |x| p x }

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#!/bin/sh

# This goes in bin/setup

npm install --save \
  gulp \
  browserify \
  react \
  react-dom \
  babelify \

gabebw

Hey there
line two
whoa

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{-
The expression problem: Adding new data types and new functionality to
existing data types is at odds.

OOP:

* adding new data types is easy
    - just write new code, and adhere to the API

* But adding new functionality to existing data types is hard

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LYAH Chapters 5 & 6

Homework

• How did it go?
• Head/Tail/Init/Last: https://gist.github.com/gabebw/a6284db3d96612aae5a5
• Pattern Matching: https://gist.github.com/gabebw/a837caca1869ab4daafa
• Bonus: Fill in the Types: https://gist.github.com/gabebw/039ca8c2199372b811ba

Chapter 5: Recursion

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-- Added type signatures

module PatternMatching where
    import Data.Char (isUpper)

    -- `:t even` shows that `even` needs `Integral`, but nothing more precise
    -- than that
    anyEven :: (Integral a) => [a] -> Bool
    anyEven list = not $ null $ filter even list

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module PatternMatching where
    -- Return the first character of a String, or the question mark character for an
    -- empty string.
    -- > firstCharacter "hello"
    -- 'h'
    -- > firstCharacter ""
    -- '?'
    -- Hint: String is the same as [Char].
    firstCharacter :: String -> Char
    firstCharacter (c:_) = c

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module HeadTailInitLast where
    -- middle [1] == []
    -- middle [1..6] == [2, 3, 4, 5]
    middle :: [a] -> [a]
    middle s@(_:_:_:_) = tail $ init s
    middle _ = []

    -- Maybe more Rubyish:
    middle' :: [a] -> [a]
    middle' s 

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Ch 1: Basics

GHCI

• :l baby to load baby.hs
• :t (+) to show function type
  • parentheses required for infix functions

• * is an infix function (because it's punctuation)
  • so 5 * 3 is parsed exactly as * 5 3, which is really (* 5) 3

Lists