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const arrowFunction = (arg1, arg2) => {
  const result = arg1 + arg2;
  return result;
};

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lambdaFunction = lambda a, b : a + b

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document.querySelector('#myButton').addEventListner('click', function() {
  alert('click happened');
});

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const myFirstClassFunction = function(a) {
  return function(b) {
    return a + b;
  };
};

myFirstClassFunction(1)(2); // => 3

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const myFirstClassArrow = a => b => a + b;

myFirstClassArrow(1)(2); // => 3

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const add = a => b => a + b;

const increaseCounter = counter => add(1)(counter);
increaseCounter(5); // => 6

const pointFreeIncreaseCounter = add(1);
pointFreeIncreaseCounter(5); // => 6

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import {trim, upperCaseOf, lengthOf, lastLetterOf, includes, compose} from '@7urtle/lambda';

const endsWithPunctuation = input =>
  includes(lastLetterOf(input))('.?,!');

const replacePunctuationWithExclamation = input =>
  substr(lengthOf(input) - 1)(0)(input) + '!';

const addExclamationMark = input =>
  endsWithPunctuation(input)

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const filterMap = (checker, mapper, list) =>
    list.reduce(
      (acc, current) => checker(current) ? acc.push(mapper(current)) && acc : acc,
      []
    );

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const myList = [1, 2, 3];
const myChecker = a => a > 1; // filter only numbers larger than 1
const myMapper = a => a + 1; // make all numbers + 1

filterMap(myChecker, myMapper, myList); // => [3, 4]

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import {filterMap, includes, upperCaseOf} from '@7urtle/lambda';

const animals = ['Russian Turtle', 'Greek Turtle', 'House Cat'];
const onlyTurtles = includes('Turtle');

filterMap(onlyTurtles, upperCaseOf, animals);
// => ['RUSSIAN TURTLE', 'GREEK TURTLE']

filterMap(onlyTurtles)(upperCaseOf)(animals); // curried
// => ['RUSSIAN TURTLE', 'GREEK TURTLE']