Oh My Lib

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This is a library of Javascript functions created with the purpose of practicing my Javascript skills and putting into practice some less used techniques. Therefore, not all functions are done in a way that has the best possible performance because they may have been done by focusing on a specific approach for study purposes.

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Functions categories:

• Math
• Array
• Collection

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Math functions

max

Called to biggest between two passed values.

Input: (number/string, number/string)
Output: number/string

const result = max(5, 2);

//result == 5

min

Called to smaller between two passed values.

Input: (number/string, number/string)
Output: number/string

const result = min(5, 2);

//result == 2

sumAllInRange

Returns the sum of all integers between the first and the second parameters. If passed a third parameter, the result the result will be the sum of numbers starting from the first parameter but steping the passed value until reach the second parameter.

Input: (integer, integer, integer=1)
Output: number

const result = sumAllInRange(3, 99, 4);

//result == 1275

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Array functions

first

Return the first element of the array

Input: (array)
Output: number/string

const result = first([1,2,3]);

//result == 1

tail

Return the the array without the first element

Input: (array)
Output: array

const result = tail([1,2,3]);

//result == [2,3]

last

Return the last element of the array

Input: (array)
Output: number/string

const result = last([1,2,3]);

//result == 3

init

Return the the array without the last element

Input: (array)
Output: array

const result = init([1,2,3]);

//result == [1,2]

each

Called to execute some passed function over all elements of a passed array without return any result.

Input: (array, function)
Output: undefined

each([1,2,3], (value) => { console.log(value) });

filter

Returns as result a list with the elements that passed the test defined by the passed function.

Input: (array, function)
Output: array

filter([1,2,3], (value) => { return value > 1 });

//result == [2,3]

maxOfList

Called to get the biggest value between the values of a passed array.

Input: (array)
Output: number/string

const result = lib.maxOfList([5,10,2,9]);

//result == 10

maxOccurrence

Called to get the most frequent element of the array. If more than one element have the same frenquency, the first element to reach that frequency will be returned.

Input: (array)
Output: number/string

const result = lib.maxOccurrence(['a','a','c','b','c','c']);

//result == 'c'

trueValues

Returns a copy of the passed array without the falsy values. In Javascript, the falsy values are false, null, 0, "", undefined and NaN.

Input: (array)
Output: array

const result = lib.trueValues(['c', 0, null, 1]);

//result == ['c', 1]

except

Returns a copy of the passed array without the passed values.

Input: (array, number/string...)
Output: array

const result = lib.except(['a','a','c','b','c','c'], 'b', 'c');

//result == ['a', 'a']

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Collection functions

extractProperty

Called to get the value of a property with the given name of all elements of a passed larrayist.

Input: (array, string)
Output: array

const list = [
  { a: 1, b: 2, c: 3 },
  { a: 4, b: 5, c: 6 },
  { a: 7, b: 8, c: 9 },
  { a: 10, b: 11, c: 12 },
  { a: 13, b: 14, c: 15 }
];
const result = lib.extractProperty(list, 'b');

//result == [2,5,8,11,14]

maxOfProperty

Called to get the biggest value of a passed property from a passed array of objects.

Input: (array, string)
Output: number/string

const result = maxOfProperty([
  { age: 20 },
  { age: 25 },
  { age: 10 },
  { age: 40 }
], 'age');

//result == 40