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Angelos Chalaris
2017-12-19 13:32:25 +02:00
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121
README.md
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@ -17,8 +17,10 @@
* [`countOccurrences`](#countoccurrences)
* [`deepFlatten`](#deepflatten)
* [`difference`](#difference)
* [`differenceWith`](#differencewith)
* [`distinctValuesOfArray`](#distinctvaluesofarray)
* [`dropElements`](#dropelements)
* [`dropRight`](#dropright)
* [`everyNth`](#everynth)
* [`filterNonUnique`](#filternonunique)
* [`flatten`](#flatten)
@ -34,6 +36,8 @@
* [`nthElement`](#nthelement)
* [`pick`](#pick)
* [`pull`](#pull)
* [`pullAll`](#pullall)
* [`pullAtIndex`](#pullatindex)
* [`remove`](#remove)
* [`sample`](#sample)
* [`shuffle`](#shuffle)
@ -103,6 +107,7 @@
* [`cleanObj`](#cleanobj)
* [`objectFromPairs`](#objectfrompairs)
* [`objectToPairs`](#objecttopairs)
* [`select`](#select)
* [`shallowClone`](#shallowclone)
* [`truthCheckCollection`](#truthcheckcollection)
@ -235,6 +240,19 @@ const difference = (a, b) => { const s = new Set(b); return a.filter(x => !s.has
[⬆ back to top](#table-of-contents)
### differenceWith
Filters out all values from an array for which the comparator function does not return `true`.
Use `Array.filter()` and `Array.find()` to find the appropriate values.
```js
const differenceWith = (arr, val, comp) => arr.filter(a => !val.find(b => comp(a, b)))
// differenceWith([1, 1.2, 1.5, 3], [1.9, 3], (a,b) => Math.round(a) == Math.round(b)) -> [1, 1.2]
```
[⬆ back to top](#table-of-contents)
### distinctValuesOfArray
Returns all the distinct values of an array.
@ -265,6 +283,21 @@ const dropElements = (arr, func) => {
[⬆ back to top](#table-of-contents)
### dropRight
Returns a new array with `n` elements removed from the right
Check if `n` is shorter than the given array and use `Array.slice()` to slice it accordingly or return an empty array.
```js
const dropRight = (arr, n = 1) => n < arr.length ? arr.slice(0, arr.length - n) : []
//dropRight([1,2,3]) -> [1,2]
//dropRight([1,2,3], 2) -> [1]
//dropRight([1,2,3], 42) -> []
```
[⬆ back to top](#table-of-contents)
### everyNth
Returns every nth element in an array.
@ -367,15 +400,16 @@ const initial = arr => arr.slice(0, -1);
### initializeArrayWithRange
Initializes an array containing the numbers in the specified range.
Initializes an array containing the numbers in the specified range where `start` and `end` are inclusive.
Use `Array(end-start)` to create an array of the desired length, `Array.map()` to fill with the desired values in a range.
Use `Array((end + 1) - start)` to create an array of the desired length, `Array.map()` to fill with the desired values in a range.
You can omit `start` to use a default value of `0`.
```js
const initializeArrayWithRange = (end, start = 0) =>
Array.from({ length: end - start }).map((v, i) => i + start);
// initializeArrayWithRange(5) -> [0,1,2,3,4]
const initializeArrayWithRange = (end, start = 0) =>
Array.from({ length: (end + 1) - start }).map((v, i) => i + start);
// initializeArrayWithRange(5) -> [0,1,2,3,4,5]
// initializeArrayWithRange(7, 3) -> [3,4,5,6,7]
```
[⬆ back to top](#table-of-contents)
@ -474,6 +508,8 @@ Mutates the original array to filter out the values specified.
Use `Array.filter()` and `Array.includes()` to pull out the values that are not needed.
Use `Array.length = 0` to mutate the passed in array by resetting it's length to zero and `Array.push()` to re-populate it with only the pulled values.
_(For a snippet that does not mutate the original array see [`without`](#without))_
```js
const pull = (arr, ...args) => {
let pulled = arr.filter((v, i) => !args.includes(v));
@ -486,6 +522,52 @@ const pull = (arr, ...args) => {
[⬆ back to top](#table-of-contents)
### pullAll
Mutates the original array to filter out the values specified (accepts an array of values).
Use `Array.filter()` and `Array.includes()` to pull out the values that are not needed.
Use `Array.length = 0` to mutate the passed in array by resetting it's length to zero and `Array.push()` to re-populate it with only the pulled values.
```js
const pullAll = (arr, pullArr) => {
let pulled = arr.filter((v, i) => !pullArr.includes(v));
arr.length = 0; pulled.forEach(v => arr.push(v));
}
// let myArray = ['a', 'b', 'c', 'a', 'b', 'c'];
// pullAll(myArray, ['a', 'c']);
// console.log(myArray) -> [ 'b', 'b' ]
```
[⬆ back to top](#table-of-contents)
### pullAtIndex
Mutates the original array to filter out the values at the specified indexes.
Use `Array.filter()` and `Array.includes()` to pull out the values that are not needed.
Use `Array.length = 0` to mutate the passed in array by resetting it's length to zero and `Array.push()` to re-populate it with only the pulled values.
Use `Array.push()` to keep track of pulled values
```js
const pullAtIndex = (arr, pullArr) => {
let removed = [];
let pulled = arr.map((v, i) => pullArr.includes(i) ? removed.push(v) : v)
.filter((v, i) => !pullArr.includes(i))
arr.length = 0;
pulled.forEach(v => arr.push(v));
return removed;
}
// let myArray = ['a', 'b', 'c', 'd'];
// let pulled = pullAtIndex(myArray, [1, 3]);
// console.log(myArray); -> [ 'a', 'c' ]
// console.log(pulled); -> [ 'b', 'd' ]
```
[⬆ back to top](#table-of-contents)
### remove
Removes elements from an array for which the given function returns `false`.
@ -621,6 +703,8 @@ Filters out the elements of an array, that have one of the specified values.
Use `Array.filter()` to create an array excluding(using `!Array.includes()`) all given values.
_(For a snippet that mutates the original array see [`pull`](#pull))_
```js
const without = (arr, ...args) => arr.filter(v => !args.includes(v));
// without([2, 1, 2, 3], 1, 2) -> [3]
@ -658,7 +742,7 @@ Use `scrollY`, `scrollHeight` and `clientHeight` to determine if the bottom of t
```js
const bottomVisible = () =>
document.documentElement.clientHeight + window.scrollY >= document.documentElement.scrollHeight || document.documentElement.clientHeight;
document.documentElement.clientHeight + window.scrollY >= (document.documentElement.scrollHeight || document.documentElement.clientHeight);
// bottomVisible() -> true
```
@ -1144,7 +1228,7 @@ Return the number at the midpoint if `length` is odd, otherwise the average of t
```js
const median = arr => {
const mid = Math.floor(arr.length / 2), nums = arr.sort((a, b) => a - b);
const mid = Math.floor(arr.length / 2), nums = [...arr].sort((a, b) => a - b);
return arr.length % 2 !== 0 ? nums[mid] : (nums[mid - 1] + nums[mid]) / 2;
};
// median([5,6,50,1,-5]) -> 5
@ -1373,6 +1457,22 @@ const objectToPairs = obj => Object.keys(obj).map(k => [k, obj[k]]);
[⬆ back to top](#table-of-contents)
### select
Retrieve a property that indicated by the selector from object.
If property not exists returns `undefined`.
```js
const select = (from, selector) =>
selector.split('.').reduce((prev, cur) => prev && prev[cur], from);
// const obj = {selector: {to: {val: 'val to select'}}};
// select(obj, 'selector.to.val'); -> 'val to select'
```
[⬆ back to top](#table-of-contents)
### shallowClone
Creates a shallow clone of an object.
@ -1460,8 +1560,7 @@ Retuns `number` of vowels in provided string.
Use a regular expression to count number of vowels `(A, E, I, O, U)` in a `string`.
```js
const countVowels = str =>
return (str.match(/[aeiou]/ig) || []).length;
const countVowels = str => (str.match(/[aeiou]/ig) || []).length;
// countVowels('foobar') -> 3
// countVowels('gym') -> 0
```
@ -1503,11 +1602,11 @@ const fromCamelCase = (str, separator = '_') =>
Reverses a string.
Use array destructuring and `Array.reverse()` to reverse the order of the characters in the string.
Use `split('')` and `Array.reverse()` to reverse the order of the characters in the string.
Combine characters to get a string using `join('')`.
```js
const reverseString = str => [...str].reverse().join('');
const reverseString = str => str.split('').reverse().join('');
// reverseString('foobar') -> 'raboof'
```

88
docs/index.html
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@ -42,8 +42,10 @@
<a class="sublink-1" href="#countoccurrences">countOccurrences</a>
<a class="sublink-1" href="#deepflatten">deepFlatten</a>
<a class="sublink-1" href="#difference">difference</a>
<a class="sublink-1" href="#differencewith">differenceWith</a>
<a class="sublink-1" href="#distinctvaluesofarray">distinctValuesOfArray</a>
<a class="sublink-1" href="#dropelements">dropElements</a>
<a class="sublink-1" href="#dropright">dropRight</a>
<a class="sublink-1" href="#everynth">everyNth</a>
<a class="sublink-1" href="#filternonunique">filterNonUnique</a>
<a class="sublink-1" href="#flatten">flatten</a>
@ -59,6 +61,8 @@
<a class="sublink-1" href="#nthelement">nthElement</a>
<a class="sublink-1" href="#pick">pick</a>
<a class="sublink-1" href="#pull">pull</a>
<a class="sublink-1" href="#pullall">pullAll</a>
<a class="sublink-1" href="#pullatindex">pullAtIndex</a>
<a class="sublink-1" href="#remove">remove</a>
<a class="sublink-1" href="#sample">sample</a>
<a class="sublink-1" href="#shuffle">shuffle</a>
@ -128,6 +132,7 @@
</h3><a class="sublink-1" href="#cleanobj">cleanObj</a>
<a class="sublink-1" href="#objectfrompairs">objectFromPairs</a>
<a class="sublink-1" href="#objecttopairs">objectToPairs</a>
<a class="sublink-1" href="#select">select</a>
<a class="sublink-1" href="#shallowclone">shallowClone</a>
<a class="sublink-1" href="#truthcheckcollection">truthCheckCollection</a>
@ -210,6 +215,12 @@ Recursively flatten each element that is an array.</p>
<pre><code class="language-js">const difference = (a, b) =&gt; { const s = new Set(b); return a.filter(x =&gt; !s.has(x)); };
// difference([1,2,3], [1,2,4]) -&gt; [3]
</code></pre>
</div></div><br/><div class="card fluid"><div class="section double-padded"><h3 id="differencewith">differenceWith</h3></div><div class="section double-padded">
<p>Filters out all values from an array for which the comparator function does not return <code>true</code>.</p>
<p>Use <code>Array.filter()</code> and <code>Array.find()</code> to find the appropriate values.</p>
<pre><code class="language-js">const differenceWith = (arr, val, comp) =&gt; arr.filter(a =&gt; !val.find(b =&gt; comp(a, b)))
// differenceWith([1, 1.2, 1.5, 3], [1.9, 3], (a,b) =&gt; Math.round(a) == Math.round(b)) -&gt; [1, 1.2]
</code></pre>
</div></div><br/><div class="card fluid"><div class="section double-padded"><h3 id="distinctvaluesofarray">distinctValuesOfArray</h3></div><div class="section double-padded">
<p>Returns all the distinct values of an array.</p>
<p>Use ES6 <code>Set</code> and the <code>...rest</code> operator to discard all duplicated values.</p>
@ -218,14 +229,22 @@ Recursively flatten each element that is an array.</p>
</code></pre>
</div></div><br/><div class="card fluid"><div class="section double-padded"><h3 id="dropelements">dropElements</h3></div><div class="section double-padded">
<p>Removes elements in an array until the passed function returns <code>true</code>. Returns the remaining elements in the array.</p>
<p>Loop through the array, using <code>Array.shift()</code> to drop the first element of the array until the returned value from the function is <code>true</code>.
<p>Loop through the array, using <code>Array.slice()</code> to drop the first element of the array until the returned value from the function is <code>true</code>.
Returns the remaining elements.</p>
<pre><code class="language-js">const dropElements = (arr, func) =&gt; {
while (arr.length &gt; 0 &amp;&amp; !func(arr[0])) arr.shift();
while (arr.length &gt; 0 &amp;&amp; !func(arr[0])) arr = arr.slice(1);
return arr;
};
// dropElements([1, 2, 3, 4], n =&gt; n &gt;= 3) -&gt; [3,4]
</code></pre>
</div></div><br/><div class="card fluid"><div class="section double-padded"><h3 id="dropright">dropRight</h3></div><div class="section double-padded">
<p>Returns a new array with <code>n</code> elements removed from the right</p>
<p>Check if <code>n</code> is shorter than the given array and use <code>Array.slice()</code> to slice it accordingly or return an empty array.</p>
<pre><code class="language-js">const dropRight = (arr, n = 1) =&gt; n &lt; arr.length ? arr.slice(0, arr.length - n) : []
//dropRight([1,2,3]) -&gt; [1,2]
//dropRight([1,2,3], 2) -&gt; [1]
//dropRight([1,2,3], 42) -&gt; []
</code></pre>
</div></div><br/><div class="card fluid"><div class="section double-padded"><h3 id="everynth">everyNth</h3></div><div class="section double-padded">
<p>Returns every nth element in an array.</p>
<p>Use <code>Array.filter()</code> to create a new array that contains every nth element of a given array.</p>
@ -278,12 +297,13 @@ Use <code>Array.reduce()</code> to create an object, where the keys are produced
// initial([1,2,3]) -&gt; [1,2]
</code></pre>
</div></div><br/><div class="card fluid"><div class="section double-padded"><h3 id="initializearraywithrange">initializeArrayWithRange</h3></div><div class="section double-padded">
<p>Initializes an array containing the numbers in the specified range.</p>
<p>Use <code>Array(end-start)</code> to create an array of the desired length, <code>Array.map()</code> to fill with the desired values in a range.
<p>Initializes an array containing the numbers in the specified range where <code>start</code> and <code>end</code> are inclusive.</p>
<p>Use <code>Array((end + 1) - start)</code> to create an array of the desired length, <code>Array.map()</code> to fill with the desired values in a range.
You can omit <code>start</code> to use a default value of <code>0</code>.</p>
<pre><code class="language-js">const initializeArrayWithRange = (end, start = 0) =&gt;
Array.from({ length: end - start }).map((v, i) =&gt; i + start);
// initializeArrayWithRange(5) -&gt; [0,1,2,3,4]
<pre><code class="language-js">const initializeArrayWithRange = (end, start = 0) =&gt;
Array.from({ length: (end + 1) - start }).map((v, i) =&gt; i + start);
// initializeArrayWithRange(5) -&gt; [0,1,2,3,4,5]
// initializeArrayWithRange(7, 3) -&gt; [3,4,5,6,7]
</code></pre>
</div></div><br/><div class="card fluid"><div class="section double-padded"><h3 id="initializearraywithvalues">initializeArrayWithValues</h3></div><div class="section double-padded">
<p>Initializes and fills an array with the specified values.</p>
@ -334,6 +354,7 @@ Omit the second argument, <code>n</code>, to get the first element of the array.
<p>Mutates the original array to filter out the values specified.</p>
<p>Use <code>Array.filter()</code> and <code>Array.includes()</code> to pull out the values that are not needed.
Use <code>Array.length = 0</code> to mutate the passed in array by resetting it's length to zero and <code>Array.push()</code> to re-populate it with only the pulled values.</p>
<p><em>(For a snippet that does not mutate the original array see <a href="#without"><code>without</code></a>)</em></p>
<pre><code class="language-js">const pull = (arr, ...args) =&gt; {
let pulled = arr.filter((v, i) =&gt; !args.includes(v));
arr.length = 0; pulled.forEach(v =&gt; arr.push(v));
@ -342,6 +363,38 @@ Use <code>Array.length = 0</code> to mutate the passed in array by resetting it'
// pull(myArray, 'a', 'c');
// console.log(myArray) -&gt; [ 'b', 'b' ]
</code></pre>
</div></div><br/><div class="card fluid"><div class="section double-padded"><h3 id="pullall">pullAll</h3></div><div class="section double-padded">
<p>Mutates the original array to filter out the values specified (accepts an array of values).</p>
<p>Use <code>Array.filter()</code> and <code>Array.includes()</code> to pull out the values that are not needed.
Use <code>Array.length = 0</code> to mutate the passed in array by resetting it's length to zero and <code>Array.push()</code> to re-populate it with only the pulled values.</p>
<pre><code class="language-js">const pullAll = (arr, pullArr) =&gt; {
let pulled = arr.filter((v, i) =&gt; !pullArr.includes(v));
arr.length = 0; pulled.forEach(v =&gt; arr.push(v));
}
// let myArray = ['a', 'b', 'c', 'a', 'b', 'c'];
// pullAll(myArray, ['a', 'c']);
// console.log(myArray) -&gt; [ 'b', 'b' ]
</code></pre>
</div></div><br/><div class="card fluid"><div class="section double-padded"><h3 id="pullatindex">pullAtIndex</h3></div><div class="section double-padded">
<p>Mutates the original array to filter out the values at the specified indexes.</p>
<p>Use <code>Array.filter()</code> and <code>Array.includes()</code> to pull out the values that are not needed.
Use <code>Array.length = 0</code> to mutate the passed in array by resetting it's length to zero and <code>Array.push()</code> to re-populate it with only the pulled values.
Use <code>Array.push()</code> to keep track of pulled values</p>
<pre><code class="language-js">const pullAtIndex = (arr, pullArr) =&gt; {
let removed = [];
let pulled = arr.map((v, i) =&gt; pullArr.includes(i) ? removed.push(v) : v)
.filter((v, i) =&gt; !pullArr.includes(i))
arr.length = 0;
pulled.forEach(v =&gt; arr.push(v));
return removed;
}
// let myArray = ['a', 'b', 'c', 'd'];
// let pulled = pullAtIndex(myArray, [1, 3]);
// console.log(myArray); -&gt; [ 'a', 'c' ]
// console.log(pulled); -&gt; [ 'b', 'd' ]
</code></pre>
</div></div><br/><div class="card fluid"><div class="section double-padded"><h3 id="remove">remove</h3></div><div class="section double-padded">
<p>Removes elements from an array for which the given function returns <code>false</code>.</p>
<p>Use <code>Array.filter()</code> to find array elements that return truthy values and <code>Array.reduce()</code> to remove elements using <code>Array.splice()</code>.
@ -411,6 +464,7 @@ This method also works with strings.</p>
</div></div><br/><div class="card fluid"><div class="section double-padded"><h3 id="without">without</h3></div><div class="section double-padded">
<p>Filters out the elements of an array, that have one of the specified values.</p>
<p>Use <code>Array.filter()</code> to create an array excluding(using <code>!Array.includes()</code>) all given values.</p>
<p><em>(For a snippet that mutates the original array see <a href="#pull"><code>pull</code></a>)</em></p>
<pre><code class="language-js">const without = (arr, ...args) =&gt; arr.filter(v =&gt; !args.includes(v));
// without([2, 1, 2, 3], 1, 2) -&gt; [3]
</code></pre>
@ -433,7 +487,7 @@ If lengths of the argument-arrays vary, <code>undefined</code> is used where no
<p>Returns <code>true</code> if the bottom of the page is visible, <code>false</code> otherwise.</p>
<p>Use <code>scrollY</code>, <code>scrollHeight</code> and <code>clientHeight</code> to determine if the bottom of the page is visible.</p>
<pre><code class="language-js">const bottomVisible = () =&gt;
document.documentElement.clientHeight + window.scrollY &gt;= document.documentElement.scrollHeight || document.documentElement.clientHeight;
document.documentElement.clientHeight + window.scrollY &gt;= (document.documentElement.scrollHeight || document.documentElement.clientHeight);
// bottomVisible() -&gt; true
</code></pre>
</div></div><br/><div class="card fluid"><div class="section double-padded"><h3 id="currenturl">currentURL</h3></div><div class="section double-padded">
@ -708,7 +762,7 @@ The GCD formula uses recursion.</p>
<p>Find the middle of the array, use <code>Array.sort()</code> to sort the values.
Return the number at the midpoint if <code>length</code> is odd, otherwise the average of the two middle numbers.</p>
<pre><code class="language-js">const median = arr =&gt; {
const mid = Math.floor(arr.length / 2), nums = arr.sort((a, b) =&gt; a - b);
const mid = Math.floor(arr.length / 2), nums = [...arr].sort((a, b) =&gt; a - b);
return arr.length % 2 !== 0 ? nums[mid] : (nums[mid - 1] + nums[mid]) / 2;
};
// median([5,6,50,1,-5]) -&gt; 5
@ -842,6 +896,15 @@ Also if you give it a special key (<code>childIndicator</code>) it will search d
<pre><code class="language-js">const objectToPairs = obj =&gt; Object.keys(obj).map(k =&gt; [k, obj[k]]);
// objectToPairs({a: 1, b: 2}) -&gt; [['a',1],['b',2]])
</code></pre>
</div></div><br/><div class="card fluid"><div class="section double-padded"><h3 id="select">select</h3></div><div class="section double-padded">
<p>Retrieve a property that indicated by the selector from object.</p>
<p>If property not exists returns <code>undefined</code>.</p>
<pre><code class="language-js">const select = (from, selector) =&gt;
selector.split('.').reduce((prev, cur) =&gt; prev &amp;&amp; prev[cur], from);
// const obj = {selector: {to: {val: 'val to select'}}};
// select(obj, 'selector.to.val'); -&gt; 'val to select'
</code></pre>
</div></div><br/><div class="card fluid"><div class="section double-padded"><h3 id="shallowclone">shallowClone</h3></div><div class="section double-padded">
<p>Creates a shallow clone of an object.</p>
<p>Use <code>Object.assign()</code> and an empty object (<code>{}</code>) to create a shallow clone of the original.</p>
@ -890,8 +953,7 @@ Omit the <code>lowerRest</code> parameter to keep the rest of the string intact,
</div></div><br/><div class="card fluid"><div class="section double-padded"><h3 id="countvowels">countVowels</h3></div><div class="section double-padded">
<p>Retuns <code>number</code> of vowels in provided string.</p>
<p>Use a regular expression to count number of vowels <code>(A, E, I, O, U)</code> in a <code>string</code>.</p>
<pre><code class="language-js">const countVowels = str =&gt;
return (str.match(/[aeiou]/ig) || []).length;
<pre><code class="language-js">const countVowels = str =&gt; (str.match(/[aeiou]/ig) || []).length;
// countVowels('foobar') -&gt; 3
// countVowels('gym') -&gt; 0
</code></pre>
@ -914,9 +976,9 @@ Omit the second argument to use a default separator of <code>_</code>.</p>
</code></pre>
</div></div><br/><div class="card fluid"><div class="section double-padded"><h3 id="reversestring">reverseString</h3></div><div class="section double-padded">
<p>Reverses a string.</p>
<p>Use array destructuring and <code>Array.reverse()</code> to reverse the order of the characters in the string.
<p>Use <code>split('')</code> and <code>Array.reverse()</code> to reverse the order of the characters in the string.
Combine characters to get a string using <code>join('')</code>.</p>
<pre><code class="language-js">const reverseString = str =&gt; [...str].reverse().join('');
<pre><code class="language-js">const reverseString = str =&gt; str.split('').reverse().join('');
// reverseString('foobar') -&gt; 'raboof'
</code></pre>
</div></div><br/><div class="card fluid"><div class="section double-padded"><h3 id="sortcharactersinstring">sortCharactersInString</h3></div><div class="section double-padded">

5
tag_database
View File

@ -20,10 +20,12 @@ currentURL:browser
curry:function
deepFlatten:array
difference:array
differenceWith:array
digitize:math
distance:math
distinctValuesOfArray:array
dropElements:array
dropRight:array
elementIsVisibleInViewport:browser
escapeRegExp:string
everyNth:array
@ -72,8 +74,8 @@ pipe:function
powerset:math
promisify:function
pull:array
pullAtIndex:array
pullAll:array
pullAtIndex:array
randomIntegerInRange:math
randomNumberInRange:math
readFileLines:node
@ -85,6 +87,7 @@ round:math
runPromisesInSeries:function
sample:array
scrollToTop:browser
select:object
shallowClone:object
shuffle:array
similarity:array