The inverse operation of Object.prototype.entries() This takes an array of [property, value] arrays and returns an object.

Checklist

• implementation
• tests
• jsdoc

Details

const.log(objects.fromEntries([['age', 12034], ['name', 'Trair'],['state', 'Floating']]));
> { age: 12034, name: 'Trair', state: 'Floating' }

References

• Object.fromEntries - MDN
• _.fromPairs - Lodash

In GitLab by @evanplaice on Jan 18, 2019, 23:07

CI testing makes eases the burden of collaboration.

• add Travis-CI configuration
• add status tag to README.md

The find() method returns the value of the first element in the provided array that satisfies the provided testing function.

Checklist

• implementation
• tests
• jsdoc

Details

var array1 = [5, 12, 8, 130, 44];

var found = array1.find(function(element) {
  return element > 10;
});

console.log(found);
// expected output: 12

References

• Array.prototype.find - MDN
• _.find - Lodash

Expected behaviour

The current implementation flattens the output

Actual behaviour

Is this correct?

References

endsWith('abc', 'f') returns true

Environment

• Platform: Node
• Version: 10.15.3
• Operator: Ubuntu

Steps to reproduce

• call function endsWith with arguments 'abc', and 'f'

Expected behaviour

should return false

Actual behaviour

returns true

Code

Seems like code could be replaced with:

const endsWith = (string, substr = '') =>
  string.substr(string.length - substr.length) === substr

Tap iterates through the values and applies a supplied function to each value without mutating the data.

Tap is an exception to the 'only use reduce' rule because reduce would add inefficiency.

Checklist

• implemented
• documented
• tested
• check style

References

• Array.prototype.forEach - MDN
• _.tap - Lodash

Currently, this lib is written as ES+ with the dist files and tests being provided as CJS.

Now that Node.JS has experimental support for ESM (EcmaScript Modules), see if it's viable to run/develop/test the code natively in ES6.

Milestones

• convert tests to ES
• remove chokodir watcher
• verify the import entry-point works

Adds padding to the end of a string

Milestones

• implemented
• documented
• tested
• check style

References

• String.prototype.padEnd - MDN
• _.padEnd - Lodash

Notice: The existing implementation doesn't match spec. Feel free to use it or trash it.

The flat() method creates a new array with all sub-array elements concatenated into it recursively up to the specified depth.

Checklist

• implementation
• tests
• jsdoc

Details

Should this be implemented iteratively or recursively. Study the MDN documentation in more depth before implementing.

References

• Array.prototype.flat - MDN
• _.flatten - Lodash

Filters an object by key to only include properties whitelisted by the second arg

Milestones

• implementation
• tests
• jsdoc

Details

To accomplish this, the object needs to be:

• converted to an 2D array using Object.Entries()
• filtered by key
• converted back to an object

Due to the reliance on Object.entries() this function may not be compatible with some browsers.

References

• Object.entries - MDN

Performs reduce on an array in reverse order (last->first)

Checklist

• implemented
• documented
• tested
• linted

Details

References

• Array.prototype.reduceRight - MDN
• _.reduceRight - Lodash

some calls a function (the "test" function, defined by you) on each element of an array, and returns a boolean indicating whether or not the test function returned a truthy value for any element in the array. It "short circuits" as much computation as possible by terminating the array iteration as soon as an element is encountered for which the test function returns a truthy value

Checklist

• implementation
• tests
• jsdoc

Details

function gotMilk(array) {
 return array.some((x) => x === 'milk');
}

gotMilk(['juice', 'water']); // false
gotMilk(['juice', 'milk', 'water']); // true

References

• Array.prototype.some - MDN
• _.some - Lodash

In GitLab by @evanplaice on Jan 18, 2019, 23:06

• fix r/nexted/nested/
• add links for ISSUE_TEMPLATES

Find the index of the last item that matches or -1 if there is no match.

Checklist

• implementation
• tests
• jsdoc

Details

References

• _.findLastIndex - Lodash

In GitLab by @evanplaice on Jan 18, 2019, 23:07

Add templates for the following

• ISSUE_TEMPLATE
• PULL_REQUEST_TEMPLATE
• Discussion()
• Type()
• Operator()

In GitLab by @evanplaice on Jan 18, 2019, 23:07

Update README with more detailed links to the operator descriptions

Takes an array of similar values and returns an object mapping each unique item to the number of items it occurs in the array.

Checklist

• implementation
• tests
• jsdoc

Details

Reference implementation

const input = ['a', 'b', 'a', 'c', 'a', 'c', 'b'];
const frequencies = input.reduce((acc, curr) => {
  acc[curr] = !acc[curr] ? 1 : ++acc[curr];
  return acc;
}, {});
console.log(frequencies);
> {
>   a: 3,
>   b: 2,
>   c: 2
> }

References

• tweet - Twitter

Adds padding to the start of a string

Milestones

• implemented
• documented
• tested
• check style

References

• String.prototype.padStart - MDN
• _.padStart - Lodash

In GitLab by @evanplaice on Jan 19, 2019, 00:20

This project is still pointing to the now closed GitHub page

Search a string to see if it ends with another string

Milestones

• implemented
• documented
• tested
• check style

References

• String.prototype.endsWith - MDN
• _.endsWith - Lodash

The indexOf method returns the index within the calling String object of the first occurrence of the specified value, starting the search at fromIndex. Returns -1 if the value is not found.

Checklist

• implementation
• tests
• jsdoc

Details

var paragraph = 'The quick brown fox jumps over the lazy dog. If the dog barked, was it really lazy?';

var searchTerm = 'dog';
var indexOfFirst = paragraph.indexOf(searchTerm);

console.log('The index of the first "' + searchTerm + '" from the beginning is ' + indexOfFirst);
// expected output: "The index of the first "dog" from the beginning is 40"

console.log('The index of the 2nd "' + searchTerm + '" is ' + paragraph.indexOf(searchTerm, (indexOfFirst + 1)));
// expected output: "The index of the 2nd "dog" is 52"

References

• String.prototype.indexOf - MDN

Reverses the input string

Checklist

• implemented
• documented
• tested
• linted

Details

Takes an input string and reverses it's character order using reduce.

Flatten takes an array containing n-levels of nested arrays and flattens them into a one-dimensional array.

Checklist

• implementation
• tests
• jsdoc

Details

Should this be implemented iteratively or recursively. Study the lodash documentation in more depth before implementing.

References

• _.flatten()

The every() method tests whether all elements in the array pass the test implemented by the provided function. It returns a Boolean value.

It always returns true if the array is empty

Checklist

• implementation
• tests
• jsdoc

Details

function isBelowThreshold(currentValue) {
  return currentValue < 40;
}

var array1 = [1, 30, 39, 29, 10, 13];

console.log(array1.every(isBelowThreshold));
// expected output: true

References

• Array.prototype.every - MDN
• _.every - Lodash

CHANGELOG Update Strategy

Introduction

This project could benefit from a changelog. The commit history is pretty clean so the ideal solution would be to somehow add the capability to compile a list of changes using the commit titles and hand-edit out any extra crap.

Please comment below if you have any suggestions.

References

(Add Reference Links)

Gets all but the last element of a the array

Checklist

• implementation
• tests
• jsdoc

Details

References

• _.initial

In GitLab by @evanplaice on Jan 18, 2019, 23:07

Start mapping out the documentation structure

• Add links to README.md
• /docs/arrays.md
• /docs/objects.md
• /docs/strings.md
• /docs/html.md
• Make available via github.io

In GitLab by @evanplaice on Jan 19, 2019, 01:45

Make it so new versions are automatically published to NPM.

In GitLab by @evanplaice on Jan 19, 2019, 00:12

Make the existing templates work with GitLab and add missing templates

Milestones

• New Operator Template
• Bug Template
• Enhancement Template
• Merge Request Template
• New Type Template

Breaks an array up into chunks of a specified size

Checklist

• implemented
• documented
• tested
• linted

Details

References

• _.chunk - Lodash

The findIndex() method returns the index of the first element in the array that satisfies the provided testing function. Otherwise, it returns -1, indicating that no element passed the test.

Checklist

• implementation
• tests
• jsdoc

Details

var array1 = [5, 12, 8, 130, 44];

function isLargeNumber(element) {
  return element > 13;
}

console.log(array1.findIndex(isLargeNumber));
// expected output: 3

References

• Array.prototype.findIndex - MDN
• _.findIndex - Lodash

The indexOf method returns the first index at which a given element can be found in the array, or -1 if it is not present.

Checklist

• implemented
• documented
• tested
• linted

Details

var beasts = ['ant', 'bison', 'camel', 'duck', 'bison'];

console.log(beasts.indexOf('bison'));
// expected output: 1

// start from index 2
console.log(beasts.indexOf('bison', 2));
// expected output: 4

console.log(beasts.indexOf('giraffe'));
// expected output: -1

References

• Array.prototype.indexOf - MDN
• _.indexOf - Lodash

In GitLab by @evanplaice on Jan 20, 2019, 03:45

Add CONTRUBUTING

Extract the contributor instructions into a separate file. Remove old links to GitHub templates.

In GitLab by @evanplaice on Jan 19, 2019, 01:33

Update the CI badge to show the GitLab-CI status

Search a string to see if it includes another string

Milestones

• implementation
• tests
• jsdoc

References

• String.prototype.includes - MDN

Fills a range of items in the array with a specified value.

Checklist

• implemented
• documented
• tested
• linted

Details

References

• Array.prototype.fill - MDN
• _.fill - Lodash

Concetenate any number of arrays to any level of depth

Checklist

• implemented
• documented
• tested
• linted

Details

References

• Array.prototype.concat - MDN
• _.concat - Lodash

In GitLab by @evanplaice on Jan 18, 2019, 23:57

Migrating from GitHub means Travis-CI is no longer an option.

Change the configuration to so this project runs CI through GitLab instead.

Milestones

• Remove Travis-CI configuration
• Add GitLab-CI configuration

Find the difference between the input array and the included values

Checklist

• implemented
• documented
• tested
• linted

Details

References

• _.difference - Lodash

Gets the first element of the array

Checklist

• implementation
• tests
• jsdoc

Details

References

• _.head

Creates a slice of an array with a specified number of items dropped from the start.

Checklist

• implemented
• documented
• tested
• linted

Details

References

• _.dropRight - Lodash

Filters an object by key to only include properties not blacklisted by the second arg

Milestones

• implementation
• tests
• jsdoc

Details

To accomplish this, the object needs to be:

• converted to an 2D array using Object.Entries()
• filtered by key
• converted back to an object

Due to the reliance on Object.entries() this function may not be compatible with some browsers.

References

• Object.entries - MDN

In GitLab by @evanplaice on Jan 18, 2019, 23:07

• npm version
• github version

Creates a slice of an array with a specified number of items dropped from the start.

Checklist

• implemented
• documented
• tested
• linted

Details

References

• _.drop - Lodash

Creates an array of unique values that are included in all given arrays

Checklist

• implementation
• tests
• jsdoc

Details

One possible approach:

Use something like frequency then filter the results so only the values that have the frequency of input.length are returned.

References

• _.intersection - Lodash

Repeats the input string a specified number of times

Milestones

• implementation
• tests
• jsdoc

References

• String.prototype.repeat - MDN
• _.repeat - Lodash

Takes a two-dimensional array, and a predicate. The two-dimensional array should contain two arrays of equal length. The values of each array are compared using the predicate.

Milestones

• implemented
• documented
• tested
• check style

Details

Add code snippets and/or a more in-depth description of the implementation details

References

• Array.prototype.reverse - MDN
• _.reverse - Lodash

To quote the C#/Linq documentation for Zip:

The method merges each element of the first sequence with an element that has the same index in the second sequence. If the sequences do not have the same number of elements, the method merges sequences until it reaches the end of one of them. For example, if one sequence has three elements and the other one has four, the result sequence will have only three elements.

Milestones

• implementation
• tests
• jsdoc

Details

References

• _.zip - Lodash
• Enumerable.Zip - MSDN

Filters all the falsy values (ie null, undefined, false, NaN, 0, "") out of an array.

Checklist

• implemented
• documented
• tested
• linted

Details

References

• _compact - Lodash

Check to see if a string starts with another string.

Milestones

• implemented
• documented
• tested
• check style

References

• String.prototype.startsWith - MDN
• _.startsWith