Fast, generic JavaScript/node.js utility functions.
Install with npm
$ npm i utils --save
(Table of contents generated by verb)
Utils grouped by collection
The top level export gives you an object with utils grouped into collections, like array, object, math, etc:
var utils = require('utils');
//=> {array: {flatten: [function], ...}, collection: {...}}
See example.md for an example of the utils object.
Get all utils on one object
If you want all utils on a single object (e.g. not grouped by collection):
// all utils are on the `_` property
var utils = require('utils')._;
Only get a specific collection
If you just want the string or object utils:
var string = require('utils').string;
var object = require('utils').object;
Returns all of the items in an array after the specified index.
Params
array {Array}: Collectionn {Number}: Starting index (number of items to exclude)returns {Array}: Array exluding n items.Example
after(['a', 'b', 'c'], 1)
//=> ['c']
Cast the give value to an array.
Params
val {*}returns {Array}Example
arrayify('abc')
//=> ['abc']
arrayify(['abc'])
//=> ['abc']
Returns all of the items in an array up to the specified number Opposite of <%= after() %.
Params
array {Array}n {Number}returns {Array}: Array excluding items after the given number.Example
before(['a', 'b', 'c'], 2)
//=> ['a', 'b']
Remove all falsey values from an array.
Params
arr {Array}returns {Array}Example
compact([null, a, undefined, 0, false, b, c, '']);
//=> [a, b, c]
Return the difference between the first array and additional arrays.
Params
a {Array}b {Array}returns {Array}Example
var a = ['a', 'b', 'c', 'd'];
var b = ['b', 'c'];
diff(a, b);
//=> ['a', 'd']
Loop over each item in an array and call the given function on every element.
Params
array {Array}fn {Function}thisArg {Object}: Optionally pass a thisArg to be used as the context in which to call the function.returns {Array}Example
each(['a', 'b', 'c'], function (ele) {
return ele + ele;
});
//=> ['aa', 'bb', 'cc']
each(['a', 'b', 'c'], function (ele, i) {
return i + ele;
});
//=> ['0a', '1b', '2c']
Returns the first item, or first n items of an array.
Params
array {Array}n {Number}: Number of items to return, starting at 0.returns {Array}Example
first(['a', 'b', 'c', 'd', 'e'], 2)
//=> ['a', 'b']
Recursively flatten an array or arrays. Uses the fastest implementation of array flatten for node.js
Params
array {Array}returns {Array}: Flattened arrayExample
flatten(['a', ['b', ['c']], 'd', ['e']]);
//=> ['a', 'b', 'c', 'd', 'e']
Loop over each item in an array and call the given function on every element.
Params
array {Array}fn {Function}thisArg {Object}: Optionally pass a thisArg to be used as the context in which to call the function.returns {Array}Example
forEach(['a', 'b', 'c'], function (ele) {
return ele + ele;
});
//=> ['aa', 'bb', 'cc']
forEach(['a', 'b', 'c'], function (ele, i) {
return i + ele;
});
//=> ['0a', '1b', '2c']
Returns true if the given value is an array.
Params
value {Array}: Value to test.Example
isArray(1);
//=> 'false'
isArray([1]);
//=> 'true'
Returns the last item, or last n items of an array.
Params
array {Array}n {Number}: Number of items to return, starting with the last item.returns {Array}Example
last(['a', 'b', 'c', 'd', 'e'], 2)
//=> ['d', 'e']
Returns a new array with the results of calling the given function on every element in the array. This is a faster, node.js focused alternative to JavaScript's native array map.
Params
array {Array}fn {Function}returns {Array}Example
map(['a', 'b', 'c'], function (ele) {
return ele + ele;
});
//=> ['aa', 'bb', 'cc']
map(['a', 'b', 'c'], function (ele, i) {
return i + ele;
});
//=> ['0a', '1b', '2c']
Alternative to JavaScript's native array-slice method. Slices array from the start index up to but not including the end index.
Params
array {Array}: the array to slice.start {Number}: Optionally define the starting index.end {Number}: Optionally define the ending index.Example
var arr = ['a', 'b', 'd', 'e', 'f', 'g', 'h', 'i', 'j'];
slice(arr, 3, 6);
//=> ['e', 'f', 'g']
Return an array free of duplicate values. Fastest ES5 implementation.
Params
array {Array}: The array to uniquifyreturns {Array}: With all union values.Example
union(['a', 'b', 'c', 'c']);
//=> ['a', 'b', 'c']
Return an array free of duplicate values. Fastest ES5 implementation.
Params
array {Array}: The array to uniquifyreturns {Array}: With all unique values.Example
unique(['a', 'b', 'c', 'c']);
//=> ['a', 'b', 'c']
Returns true if value exists in the given string, array
or object. See [any] for documentation.
Params
value {*}target {*}options {Object}Return true if collection contains value
Params
collection {Array|Object}string {*}returns {Boolean}Try to read the given filepath, fail silently and return null
when a file doesn't exist. Slightly faster than using fs.existsSync.
Params
fp {String}: Path of the file to read.returns {String|Null}: the utf8 contents string, or null if an error is thrown.Try to read the given directory. Wraps fs.readdirSync() with
a try/catch, so it fails silently instead of throwing when the
directory doesn't exist.
Params
dir {String}: Starting directoryreturns {Array}: Array of files.Try to require the given file, returning null if not successful
instead of throwing an error.
Params
fp {String}: File path of the file to requirereturns {*}: Returns the module function/object, or null if not found.Returns the first argument passed to the function.
returns {*}A "no-operation" function. Returns undefined regardless
of the arguments it receives.
returns {undefined}Partially applies arguments that will be appended to those provided to the returned function.
Params
ctx {Object}: Optionally supply an invocation context for the returned function.fn {Function}: The function to which arguments should be partially applied.arguments __{...}*: List of arguments to be partially applied.returns {Function}: Returns a function with partially applied arguments.Example
function fullname(first, last) {
return first + ' ' + last;
}
var name = partialRight(fn, 'Woodward');
name('Brian');
//=> 'Brian Woodward'
Returns true if any value exists, false if empty. Works for booleans, functions, numbers, strings, nulls, objects and arrays.
Params
object {Object}: The object to check for valuevalue {*}: the value to look forreturns {Boolean}: True if any values exists.Example
hasValues('a');
//=> true
hasValues('');
//=> false
hasValues(1);
//=> true
hasValues({a: 'a'}});
//=> true
hasValues({}});
//=> false
hasValues(['a']);
//=> true
Returns true if the given value is empty, false if any value exists. Works for booleans, functions, numbers, strings, nulls, objects and arrays.
Params
object {Object}: The object to check for valuevalue {*}: the value to look forreturns {Boolean}: False if any values exists.Example
isEmpty('a');
//=> false
isEmpty('');
//=> true
isEmpty(1);
//=> false
isEmpty({a: 'a'});
//=> false
isEmpty({});
//=> true
isEmpty(['a']);
//=> false
Return true if the given value is an object with keys.
Params
value {Object}: The value to check.returns {Boolean}Example
isObject(['a', 'b', 'c'])
//=> 'false'
isObject({a: 'b'})
//=> 'true'
Return true if the given value is an object with keys.
Params
value {Object}: The value to check.returns {Boolean}Example
isPlainObject(Object.create({}));
//=> true
isPlainObject(Object.create(Object.prototype));
//=> true
isPlainObject({foo: 'bar'});
//=> true
isPlainObject({});
//=> true
Returns the sum of all numbers in the given array.
Params
array {Array}: Array of numbers to add up.returns {Number}Example
sum([1, 2, 3, 4, 5])
//=> '15'
Extend object with properties of other objects
Params
object {Object}: The target object. Pass an empty object to shallow clone.objects {Object}returns {Object}Extend o with properties of other objects.
Params
o {Object}: The target object. Pass an empty object to shallow clone.objects {Object}returns {Object}Returns a copy of the given obj filtered to have only enumerable properties that have function values.
Params
obj {Object}returns {Object}Example
functions({a: 'b', c: function() {}});
//=> {c: function() {}}
Return true if key is an own, enumerable property of the given obj.
Params
key {String}obj {Object}: Optionally pass an object to check.returns {Boolean}Example
hasOwn(obj, key);
Return an array of keys for the given obj. Uses Object.keys
when available, otherwise falls back on forOwn.
Params
obj {Object}returns {Array}: Array of keys.Returns new object where each value is the result of
calling the a callback function.
Params
cb {Function}: Callback functioncbreturns {Object}Recursively combine the properties of o with the
properties of other objects.
Params
o {Object}: The target object. Pass an empty object to shallow clone.objects {Object}returns {Object}Returns a list of all enumerable properties of obj that have function
values
Params
obj {Object}returns {Array}Reduces an object to a value that is the accumulated result of running each property in the object through a callback.
Params
obj {Object}: The object to iterate over.iterator {Function}: Iterator functioninitial {Object}: Initial value.thisArg {Object}: The this binding of the iterator function.returns {Object}Example
var a = {a: 'foo', b: 'bar', c: 'baz'};
reduce(a, function (acc, value, key, obj) {
// `acc`- the initial value (or value from the previous callback call),
// `value`- the of the current property,
// `key`- the of the current property, and
// `obj` - original object
acc[key] = value.toUpperCase();
return acc;
}, {});
//=> {a: 'FOO', b: 'BAR', c: 'BAZ'};
camelCase the characters in string.
Params
string {String}: The string to camelcase.returns {String}Example
camelcase("foo bar baz");
//=> 'fooBarBaz'
Center align the characters in a string using non-breaking spaces.
Params
str {String}: The string to reverse.returns {String}: Centered string.Example
centerAlign("abc");
Like trim, but removes both extraneous whitespace and non-word characters from the beginning and end of a string.
Params
string {String}: The string to chop.returns {String}Example
chop("_ABC_");
//=> 'ABC'
chop("-ABC-");
//=> 'ABC'
chop(" ABC ");
//=> 'ABC'
Count the number of occurrances of a substring within a string.
Params
string {String}substring {String}returns {Number}: The occurances of substring in stringExample
count("abcabcabc", "a");
//=> '3'
dash-case the characters in string. This is similar to [slugify], but [slugify] makes the string compatible to be used as a URL slug.
Params
string {String}returns {String}Example
dashcase("a b.c d_e");
//=> 'a-b-c-d-e'
dot.case the characters in string.
Params
string {String}returns {String}Example
dotcase("a-b-c d_e");
//=> 'a.b.c.d.e'
Truncate a string to the specified length, and append it with an elipsis, ….
Params
str {String}length {Number}: The desired length of the returned string.ch {String}: Optionally pass custom characters to append. Default is ….returns {String}: The truncated string.Example
ellipsis("<span>foo bar baz</span>", 7);
//=> 'foo bar…'
Replace spaces in a string with hyphens. This
Params
string {String}returns {String}Example
hyphenate("a b c");
//=> 'a-b-c'
Returns true if the value is a string.
Params
val {String}returns {Boolean}: True if the value is a string.Example
isString('abc');
//=> 'true'
isString(null);
//=> 'false'
PascalCase the characters in string.
Params
string {String}returns {String}Example
pascalcase("foo bar baz");
//=> 'FooBarBaz'
path/case the characters in string.
Params
string {String}returns {String}Example
pathcase("a-b-c d_e");
//=> 'a/b/c/d/e'
Replace occurrences of a with b.
Params
str {String}a {String|RegExp}: Can be a string or regexp.b {String}returns {String}Example
replace("abcabc", /a/, "z");
//=> 'zbczbc'
Reverse the characters in a string.
Params
str {String}: The string to reverse.returns {String}Example
reverse("abc");
//=> 'cba'
Right align the characters in a string using non-breaking spaces.
Params
str {String}: The string to reverse.returns {String}: Right-aligned string.Example
rightAlign(str);
Sentence-case the characters in string.
Params
string {String}returns {String}Example
sentencecase("foo bar baz.");
//=> 'Foo bar baz.'
snake_case the characters in string.
Params
string {String}returns {String}Example
snakecase("a-b-c d_e");
//=> 'a_b_c_d_e'
Truncate a string by removing all HTML tags and limiting the result to the specified length.
Params
str {String}length {Number}: The desired length of the returned string.returns {String}: The truncated string.Example
truncate("<span>foo bar baz</span>", 7);
//=> 'foo bar'
Wrap words to a specified width using [word-wrap].
Params
string {String}: The string with words to wrap.object {Options}: Options to pass to [word-wrap]returns {String}: Formatted string.Example
wordwrap("a b c d e f", {width: 5, newline: '<br> '});
//=> ' a b c <br> d e f'
Please help improve code coverage by adding unit tests.
-----------------------|----------|----------|----------|----------|----------------|
File | % Stmts | % Branch | % Funcs | % Lines |Uncovered Lines |
-----------------------|----------|----------|----------|----------|----------------|
utils/ | 100 | 100 | 100 | 100 | |
index.js | 100 | 100 | 100 | 100 | |
utils/lib/ | 100 | 100 | 100 | 100 | |
index.js | 100 | 100 | 100 | 100 | |
utils/lib/array/ | 91.75 | 83.33 | 100 | 92.55 | |
after.js | 100 | 75 | 100 | 100 | |
arrayify.js | 100 | 100 | 100 | 100 | |
before.js | 100 | 75 | 100 | 100 | |
compact.js | 100 | 100 | 100 | 100 | |
difference.js | 100 | 100 | 100 | 100 | |
each.js | 100 | 100 | 100 | 100 | |
first.js | 88.89 | 83.33 | 100 | 88.24 | 27,46 |
flatten.js | 100 | 100 | 100 | 100 | |
forEach.js | 100 | 100 | 100 | 100 | |
index.js | 100 | 100 | 100 | 100 | |
indexOf.js | 76.92 | 70 | 100 | 83.33 | 23,40 |
isArray.js | 100 | 100 | 100 | 100 | |
last.js | 88.89 | 83.33 | 100 | 88.24 | 27,46 |
map.js | 100 | 100 | 100 | 100 | |
slice.js | 100 | 100 | 100 | 100 | |
sort.js | 90.91 | 87.5 | 100 | 90.91 | 27 |
union.js | 100 | 100 | 100 | 100 | |
unique.js | 100 | 100 | 100 | 100 | |
utils/lib/collection/ | 55.56 | 0 | 0 | 55.56 | |
any.js | 100 | 100 | 100 | 100 | |
contains.js | 42.86 | 0 | 0 | 42.86 | 18,19,21,22 |
index.js | 100 | 100 | 100 | 100 | |
utils/lib/fs/ | 68.75 | 100 | 66.67 | 68.75 | |
index.js | 100 | 100 | 100 | 100 | |
tryRead.js | 40 | 100 | 0 | 40 | 16,17,19 |
tryReaddir.js | 80 | 100 | 100 | 80 | 20 |
tryRequire.js | 80 | 100 | 100 | 80 | 19 |
utils/lib/function/ | 36.36 | 0 | 0 | 36.36 | |
identity.js | 50 | 100 | 0 | 50 | 12 |
index.js | 100 | 100 | 100 | 100 | |
noop.js | 50 | 100 | 0 | 50 | 13 |
partialRight.js | 16.67 | 0 | 0 | 16.67 | 26,27,28,29,30 |
utils/lib/lang/ | 100 | 100 | 100 | 100 | |
hasValues.js | 100 | 100 | 100 | 100 | |
index.js | 100 | 100 | 100 | 100 | |
isEmpty.js | 100 | 100 | 100 | 100 | |
isObject.js | 100 | 100 | 100 | 100 | |
isPlainObject.js | 100 | 100 | 100 | 100 | |
typeOf.js | 100 | 100 | 100 | 100 | |
utils/lib/math/ | 100 | 100 | 100 | 100 | |
index.js | 100 | 100 | 100 | 100 | |
sum.js | 100 | 100 | 100 | 100 | |
utils/lib/object/ | 62.77 | 46.15 | 17.65 | 61.96 | |
defaults.js | 100 | 100 | 100 | 100 | |
extend.js | 100 | 83.33 | 100 | 100 | |
filter.js | 100 | 100 | 100 | 100 | |
forIn.js | 100 | 100 | 100 | 100 | |
forOwn.js | 100 | 100 | 100 | 100 | |
functions.js | 28.57 | 0 | 0 | 28.57 | 21,23,24,25,29 |
hasOwn.js | 100 | 100 | 100 | 100 | |
index.js | 100 | 100 | 100 | 100 | |
keys.js | 33.33 | 50 | 0 | 33.33 | 16,17,18,20 |
mapValues.js | 37.5 | 100 | 0 | 37.5 | 18,19,21,22,25 |
merge.js | 100 | 75 | 100 | 100 | |
methods.js | 28.57 | 0 | 0 | 28.57 | 16,18,19,20,24 |
omit.js | 100 | 100 | 100 | 100 | |
pick.js | 100 | 100 | 100 | 100 | |
pluck.js | 75 | 100 | 0 | 75 | 17 |
prop.js | 33.33 | 100 | 0 | 33.33 | 4,5 |
reduce.js | 100 | 100 | 100 | 100 | |
result.js | 25 | 0 | 0 | 25 | 6,7,8,10,11,13 |
some.js | 30 | 0 | 0 | 30 |... 11,12,13,16 |
utils/lib/string/ | 99.28 | 96.77 | 96 | 99.1 | |
camelcase.js | 100 | 100 | 100 | 100 | |
centerAlign.js | 100 | 100 | 100 | 100 | |
chop.js | 100 | 100 | 100 | 100 | |
count.js | 100 | 100 | 100 | 100 | |
dashcase.js | 100 | 100 | 100 | 100 | |
dotcase.js | 100 | 100 | 100 | 100 | |
ellipsis.js | 100 | 100 | 100 | 100 | |
hyphenate.js | 100 | 100 | 100 | 100 | |
index.js | 100 | 100 | 100 | 100 | |
isString.js | 100 | 100 | 100 | 100 | |
pascalcase.js | 100 | 100 | 100 | 100 | |
pathcase.js | 100 | 100 | 100 | 100 | |
replace.js | 100 | 100 | 100 | 100 | |
reverse.js | 100 | 100 | 100 | 100 | |
rightAlign.js | 100 | 100 | 100 | 100 | |
sentencecase.js | 100 | 100 | 100 | 100 | |
slugify.js | 100 | 100 | 100 | 100 | |
snakecase.js | 100 | 100 | 100 | 100 | |
toString.js | 50 | 0 | 0 | 50 | 10 |
truncate.js | 100 | 100 | 100 | 100 | |
wordwrap.js | 100 | 100 | 100 | 100 | |
-----------------------|----------|----------|----------|----------|----------------|
All files | 84.54 | 80.52 | 67.16 | 83.43 | |
-----------------------|----------|----------|----------|----------|----------------|
Install dev dependencies:
$ npm i -d && npm test
Pull requests and stars are always welcome. For bugs and feature requests, please create an issue.
If you want to do a PR to add a util, please read the following first:
Adding external modules as dependencies
Do not edit the readme manually since verbis used to generate documentation.
Install dev dependencies, then run verb:
$ npm install -d && verb
Why another utils lib?
Project goals
This project depends on these great libraries. If you don't need a full utility belt for your project, any of these can be used by themselves:
true if a value exists in the given string, array or object. | homepagearray from the start index up to, but not including, the end… more | homepageObject constructor. | homepage.makeIterator() implementation in mout https://github.com/mout/mout. | homepageextend but only copies missing properties/values to the target object. | homepagepick from… more | homepageJon Schlinkert
Copyright © 2015 Jon Schlinkert Released under the MIT license.
This file was generated by verb-cli on September 23, 2015.
FAQs
Fast, generic JavaScript/node.js utility functions.
The npm package utils receives a total of 28,283 weekly downloads. As such, utils popularity was classified as popular.
We found that utils demonstrated a not healthy version release cadence and project activity because the last version was released a year ago. It has 1 open source maintainer collaborating on the project.
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