From b2e12335f8e7b321403bb6a73e79742f8a0c39d9 Mon Sep 17 00:00:00 2001 From: Wojciech Maj Date: Mon, 18 Dec 2017 00:41:26 +0100 Subject: [PATCH 01/37] Replace spread operator with split() for increased performance and compatibility --- snippets/reverseString.md | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/snippets/reverseString.md b/snippets/reverseString.md index a76c506db..5564a5897 100644 --- a/snippets/reverseString.md +++ b/snippets/reverseString.md @@ -2,10 +2,10 @@ 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' ``` From a26c70864bfac8c8634a486164dd91c5e57c0c0a Mon Sep 17 00:00:00 2001 From: Simon Legg Date: Mon, 18 Dec 2017 14:11:16 +0000 Subject: [PATCH 02/37] add reference to #without --- snippets/pull.md | 2 ++ 1 file changed, 2 insertions(+) diff --git a/snippets/pull.md b/snippets/pull.md index 4913c5082..42efe6c1b 100644 --- a/snippets/pull.md +++ b/snippets/pull.md @@ -5,6 +5,8 @@ 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)); From b4196993df2319c847d85e36ab5f176045175cd5 Mon Sep 17 00:00:00 2001 From: Simon Legg Date: Mon, 18 Dec 2017 14:14:46 +0000 Subject: [PATCH 03/37] Add reference to #pull --- snippets/without.md | 2 ++ 1 file changed, 2 insertions(+) diff --git a/snippets/without.md b/snippets/without.md index 70f2a20aa..532ec26d9 100644 --- a/snippets/without.md +++ b/snippets/without.md @@ -4,6 +4,8 @@ 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] From 8c5af9af49b4082fcd154ed0f81d3e6925a2f585 Mon Sep 17 00:00:00 2001 From: David Wu Date: Mon, 18 Dec 2017 18:11:24 +0100 Subject: [PATCH 04/37] Back to top link in footer --- static-parts/index-end.html | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/static-parts/index-end.html b/static-parts/index-end.html index 1dd086328..6ea0075e4 100644 --- a/static-parts/index-end.html +++ b/static-parts/index-end.html @@ -1,6 +1,9 @@ - + - + From 170c7381767065fa0956a964aaf933828fd9f590 Mon Sep 17 00:00:00 2001 From: David Wu Date: Mon, 18 Dec 2017 18:11:32 +0100 Subject: [PATCH 05/37] top anchor --- scripts/web-script.js | 1 + 1 file changed, 1 insertion(+) diff --git a/scripts/web-script.js b/scripts/web-script.js index edc221de3..27e84fcc4 100644 --- a/scripts/web-script.js +++ b/scripts/web-script.js @@ -60,6 +60,7 @@ try { output += '\n'; } output += `
`; + output += ` `; // Loop over tags and snippets to create the list of snippets for(let tag of [...new Set(Object.entries(tagDbData).map(t => t[1]))].filter(v => v).sort((a,b) => a.localeCompare(b))){ output +=md.render(`## ${capitalize(tag, true)}\n`).replace(/

/g,'

'); From 890cf6c22109b78f0a4163972c82772b9f017bf0 Mon Sep 17 00:00:00 2001 From: David Wu Date: Mon, 18 Dec 2017 18:12:11 +0100 Subject: [PATCH 06/37] Build website --- docs/index.html | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/docs/index.html b/docs/index.html index 7c2e08821..55dd98227 100644 --- a/docs/index.html +++ b/docs/index.html @@ -159,7 +159,7 @@ validateEmail validateNumber -

Array

+
 

Array

arrayMax

Returns the maximum value in an array.

Use Math.max() combined with the spread operator (...) to get the maximum value in the array.

@@ -1072,9 +1072,12 @@ Use Number() to check if the coercion holds.

// validateNumber('10') -> true

- +
- + From 758f8547d4e215855e094c9a5b2cb00402e1f666 Mon Sep 17 00:00:00 2001 From: taltmann42 Date: Mon, 18 Dec 2017 19:00:24 +0100 Subject: [PATCH 07/37] Create difference-with.md --- snippets/difference-with.md | 9 +++++++++ 1 file changed, 9 insertions(+) create mode 100644 snippets/difference-with.md diff --git a/snippets/difference-with.md b/snippets/difference-with.md new file mode 100644 index 000000000..70f43a5c5 --- /dev/null +++ b/snippets/difference-with.md @@ -0,0 +1,9 @@ +### Array differenceWith + +`filter`s out all values from `arr` for which the comparator `comp(a,b)` function never returns `true` + +```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] +``` From f6933702475cd3aa6ce0187d806a5d16f77552c3 Mon Sep 17 00:00:00 2001 From: taltmann42 Date: Mon, 18 Dec 2017 19:12:51 +0100 Subject: [PATCH 08/37] Create drop-right.md --- snippets/drop-right.md | 13 +++++++++++++ 1 file changed, 13 insertions(+) create mode 100644 snippets/drop-right.md diff --git a/snippets/drop-right.md b/snippets/drop-right.md new file mode 100644 index 000000000..9c162327a --- /dev/null +++ b/snippets/drop-right.md @@ -0,0 +1,13 @@ +### Array dropRight + +Returns a new array with `n` elements removed from the right + +Checks if `n` is shorter than the given array and slices it accordingly or returns an empty array + +```js +const dropRight = (arr, n = 1) => (arr.length - n ) > 0 ? arr.slice(0, arr.length - n) : [] + +//dropRight([1,2,3]) -> [1,2] +//dropRight([1,2,3], 2) -> [1] +//dropRight([1,2,3], 42) -> [] +``` From 911bf0a4dc01627e043eac4e532edcf8431a98a7 Mon Sep 17 00:00:00 2001 From: taltmann42 Date: Mon, 18 Dec 2017 19:15:51 +0100 Subject: [PATCH 09/37] Update drop-right.md shorter comparison of `n` and `arr.length` --- snippets/drop-right.md | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/snippets/drop-right.md b/snippets/drop-right.md index 9c162327a..b1f7e02ed 100644 --- a/snippets/drop-right.md +++ b/snippets/drop-right.md @@ -5,7 +5,7 @@ Returns a new array with `n` elements removed from the right Checks if `n` is shorter than the given array and slices it accordingly or returns an empty array ```js -const dropRight = (arr, n = 1) => (arr.length - n ) > 0 ? arr.slice(0, arr.length - n) : [] +const (arr, n = 1) => n < arr.length ? arr.slice(0, arr.length - n) : [] //dropRight([1,2,3]) -> [1,2] //dropRight([1,2,3], 2) -> [1] From d8c41260da61e6a5804f69cd1007dbce20ea7800 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Stefan=20Feje=C5=A1?= Date: Mon, 18 Dec 2017 20:07:44 +0100 Subject: [PATCH 10/37] Add countVowels --- snippets/countVowels.md | 12 ++++++++++++ 1 file changed, 12 insertions(+) create mode 100644 snippets/countVowels.md diff --git a/snippets/countVowels.md b/snippets/countVowels.md new file mode 100644 index 000000000..d7d98248b --- /dev/null +++ b/snippets/countVowels.md @@ -0,0 +1,12 @@ +### countVowels + +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; +// countVowels('foobar') -> 3 +// countVowels('gym') -> 0 +``` From 93096b8bdc84d32216db797d2b1bab4e58de12ad Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Stefan=20Feje=C5=A1?= Date: Mon, 18 Dec 2017 20:20:24 +0100 Subject: [PATCH 11/37] Generated readme, index and tag_database for countVowels --- README.md | 16 ++++++++++++++++ docs/index.html | 9 +++++++++ tag_database | 1 + 3 files changed, 26 insertions(+) diff --git a/README.md b/README.md index c4a6765d3..3ba0a832b 100644 --- a/README.md +++ b/README.md @@ -110,6 +110,7 @@ * [`anagrams`](#anagrams) * [`capitalize`](#capitalize) * [`capitalizeEveryWord`](#capitalizeeveryword) +* [`countVowels`](#countvowels) * [`escapeRegExp`](#escaperegexp) * [`fromCamelCase`](#fromcamelcase) * [`reverseString`](#reversestring) @@ -1452,6 +1453,21 @@ const capitalizeEveryWord = str => str.replace(/\b[a-z]/g, char => char.toUpperC [⬆ back to top](#table-of-contents) +### countVowels + +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; +// countVowels('foobar') -> 3 +// countVowels('gym') -> 0 +``` + +[⬆ back to top](#table-of-contents) + ### escapeRegExp Escapes a string to use in a regular expression. diff --git a/docs/index.html b/docs/index.html index 7c2e08821..cabdd7c23 100644 --- a/docs/index.html +++ b/docs/index.html @@ -133,6 +133,7 @@

anagrams capitalize capitalizeEveryWord +countVowels escapeRegExp fromCamelCase reverseString @@ -884,6 +885,14 @@ Omit the lowerRest parameter to keep the rest of the string intact, 
const capitalizeEveryWord = str => str.replace(/\b[a-z]/g, char => char.toUpperCase());
 // capitalizeEveryWord('hello world!') -> 'Hello World!'
+

countVowels

+

Retuns number of vowels in provided string.

+

Use a regular expression to count number of vowels (A, E, I, O, U) in a string.

+
const countVowels = str =>
+  return (str.match(/[aeiou]/ig) || []).length;
+// countVowels('foobar') -> 3
+// countVowels('gym') -> 0
+

escapeRegExp

Escapes a string to use in a regular expression.

Use replace() to escape special characters.

diff --git a/tag_database b/tag_database index f48f069b3..9f48d15cb 100644 --- a/tag_database +++ b/tag_database @@ -15,6 +15,7 @@ collatz:math compact:array compose:function countOccurrences:array +countVowels:string currentURL:browser curry:function deepFlatten:array From c30e245830233dfc3fcbcdb14554130ec152f5ed Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Stefan=20Feje=C5=A1?= Date: Mon, 18 Dec 2017 20:26:37 +0100 Subject: [PATCH 12/37] Fix small syntax typo --- CONTRIBUTING.md | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md index 4b1164232..ac39ceccc 100644 --- a/CONTRIBUTING.md +++ b/CONTRIBUTING.md @@ -24,7 +24,7 @@ Here's what you can do to help: - Follow snippet descriptions with an empty line. - **Snippet code** must be enclosed inside ` ```js ` and ` ``` `. - Remember to start your snippet's code on a new line below the opening backticks. - - Use ES6 notation to define your function. For example `const myFunction = arg1, arg2 => { }`. + - Use ES6 notation to define your function. For example `const myFunction = ( arg1, arg2 ) => { }`. - Try to keep your snippets' code short and to the point. Use modern techniques and features. Make sure to test your code before submitting. - All snippets must be followed by one (more if necessary) test case after the code, on a new line, in the form of a comment, along with the expected output. The syntax for this is `myFunction('testInput') -> 'testOutput'`. Use multiline comments only if necessary. - Try to make your function name unique, so that it does not conflict with existing snippets. @@ -57,7 +57,7 @@ Here's what you can do to help: - Use `()` if your function takes no arguments. - Use `_` if an argument inside some function (e.g. `Array.reduce()`) is not used anywhere in your code. - Specify default parameters for arguments, if necessary. It is preferred to put default parameters last unless you have pretty good reason not to. -- If your snippet's function takes variadic arguments, use `..args` (although in certain cases, it might be needed to use a different name). +- If your snippet's function takes variadic arguments, use `...args` (although in certain cases, it might be needed to use a different name). - If your snippet function's body is a single statement, omit the `return` keyword and use an expression instead. - Always use soft tabs (2 spaces), never hard tabs. - Omit curly braces (`{` and `}`) whenever possible. From 21c7e06f7fe87872e47d9cd524da220b2977da56 Mon Sep 17 00:00:00 2001 From: King Date: Mon, 18 Dec 2017 14:32:05 -0500 Subject: [PATCH 13/37] add pullAll --- snippets/pullAll.md | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) create mode 100644 snippets/pullAll.md diff --git a/snippets/pullAll.md b/snippets/pullAll.md new file mode 100644 index 000000000..d630aab99 --- /dev/null +++ b/snippets/pullAll.md @@ -0,0 +1,18 @@ +### pullAll + +This method is like pull except that it accepts an array of values to filter out before Mutating and pulling all the values from the original array. + +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' ] +``` \ No newline at end of file From 1053a662831c40316eb0b87ab65c64f88c6dc0c7 Mon Sep 17 00:00:00 2001 From: King Date: Mon, 18 Dec 2017 14:40:26 -0500 Subject: [PATCH 14/37] ran npm tagger & updated pullAll:array -> tag_database --- tag_database | 1 + 1 file changed, 1 insertion(+) diff --git a/tag_database b/tag_database index f48f069b3..d1f687a4b 100644 --- a/tag_database +++ b/tag_database @@ -71,6 +71,7 @@ pipe:function powerset:math promisify:function pull:array +pullAll:array randomIntegerInRange:math randomNumberInRange:math readFileLines:node From 957f4789820152d2bfd10a1451aa4402664a5629 Mon Sep 17 00:00:00 2001 From: King Date: Mon, 18 Dec 2017 17:42:47 -0500 Subject: [PATCH 15/37] add pullAtIndex.md --- snippets/pullAtIndex.md | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) create mode 100644 snippets/pullAtIndex.md diff --git a/snippets/pullAtIndex.md b/snippets/pullAtIndex.md new file mode 100644 index 000000000..e9efc172d --- /dev/null +++ b/snippets/pullAtIndex.md @@ -0,0 +1,24 @@ +### pullAtIndex + +This method is like pull except that it accepts an array of indexes to filter out before Mutating and pulling all the values from the original array. Which then returns an array of removed elements. + +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' ] +``` \ No newline at end of file From 06e61e311607dcf5dd33b43325df4968e53d8187 Mon Sep 17 00:00:00 2001 From: King Date: Mon, 18 Dec 2017 17:44:18 -0500 Subject: [PATCH 16/37] update tag DB with pullAtIndex:array & ran npm run tagger --- tag_database | 1 + 1 file changed, 1 insertion(+) diff --git a/tag_database b/tag_database index f48f069b3..c1a503097 100644 --- a/tag_database +++ b/tag_database @@ -71,6 +71,7 @@ pipe:function powerset:math promisify:function pull:array +pullAtIndex:array randomIntegerInRange:math randomNumberInRange:math readFileLines:node From 0128cc2a10ff0a7dfce3e4f11c04a926bd14fd42 Mon Sep 17 00:00:00 2001 From: atomiks Date: Tue, 19 Dec 2017 10:58:11 +1100 Subject: [PATCH 17/37] Make median.md immutable `.sort()` mutates the original array --- snippets/median.md | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/snippets/median.md b/snippets/median.md index fd8ca3d7c..c7eea609c 100644 --- a/snippets/median.md +++ b/snippets/median.md @@ -7,7 +7,7 @@ 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 From 60226545406e6eafc8dcef895294f117a888a5fe Mon Sep 17 00:00:00 2001 From: Larry Botha Date: Tue, 19 Dec 2017 08:52:26 +0200 Subject: [PATCH 18/37] use Array.slice instead of Array.shift --- snippets/dropElements.md | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/snippets/dropElements.md b/snippets/dropElements.md index 34138eb93..adc81d79d 100644 --- a/snippets/dropElements.md +++ b/snippets/dropElements.md @@ -2,12 +2,12 @@ Removes elements in an array until the passed function returns `true`. Returns the remaining elements in the array. -Loop through the array, using `Array.shift()` to drop the first element of the array until the returned value from the function is `true`. +Loop through the array, using `Array.slice()` to drop the first element of the array until the returned value from the function is `true`. Returns the remaining elements. ```js const dropElements = (arr, func) => { - while (arr.length > 0 && !func(arr[0])) arr.shift(); + while (arr.length > 0 && !func(arr[0])) arr = arr.slice(1); return arr; }; // dropElements([1, 2, 3, 4], n => n >= 3) -> [3,4] From ddcd2787f8f4b1c0c0d3cab6d3d65fd1b40f576e Mon Sep 17 00:00:00 2001 From: Larry Botha Date: Tue, 19 Dec 2017 08:53:18 +0200 Subject: [PATCH 19/37] build updated readme --- README.md | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/README.md b/README.md index c4a6765d3..57328c55a 100644 --- a/README.md +++ b/README.md @@ -251,12 +251,12 @@ const distinctValuesOfArray = arr => [...new Set(arr)]; Removes elements in an array until the passed function returns `true`. Returns the remaining elements in the array. -Loop through the array, using `Array.shift()` to drop the first element of the array until the returned value from the function is `true`. +Loop through the array, using `Array.slice()` to drop the first element of the array until the returned value from the function is `true`. Returns the remaining elements. ```js const dropElements = (arr, func) => { - while (arr.length > 0 && !func(arr[0])) arr.shift(); + while (arr.length > 0 && !func(arr[0])) arr = arr.slice(1); return arr; }; // dropElements([1, 2, 3, 4], n => n >= 3) -> [3,4] From 88bf2d6cf455200087c6ee276d74b70fb4382d5b Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?=E6=84=9A=E4=BA=BA=E7=A0=81=E5=A4=B4?= Date: Tue, 19 Dec 2017 14:58:08 +0800 Subject: [PATCH 20/37] code error ```js const bottomVisible = () => document.documentElement.clientHeight + window.scrollY >= (document.documentElement.scrollHeight || document.documentElement.clientHeight); // bottomVisible() -> true ``` --- snippets/bottomVisible.md | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/snippets/bottomVisible.md b/snippets/bottomVisible.md index 8e655db45..adac44881 100644 --- a/snippets/bottomVisible.md +++ b/snippets/bottomVisible.md @@ -6,6 +6,6 @@ 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 ``` From 7cd73ff2d851ad17c49d86af56c93c3fad247cc3 Mon Sep 17 00:00:00 2001 From: David Wu Date: Tue, 19 Dec 2017 10:23:25 +0100 Subject: [PATCH 21/37] Add subtitle to header --- static-parts/index-start.html | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/static-parts/index-start.html b/static-parts/index-start.html index 0aeee1e31..cc270b31f 100644 --- a/static-parts/index-start.html +++ b/static-parts/index-start.html @@ -22,8 +22,10 @@ -
-

 30 seconds of code

+
+

 30 seconds of code + Curated collection of useful Javascript snippets that you can understand in 30 seconds or less. +

From 8217f400b8a3fd64933575cbd0614eb47dc7796e Mon Sep 17 00:00:00 2001 From: David Wu Date: Tue, 19 Dec 2017 10:23:38 +0100 Subject: [PATCH 22/37] Build site --- docs/index.html | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/docs/index.html b/docs/index.html index 7c2e08821..2cead4570 100644 --- a/docs/index.html +++ b/docs/index.html @@ -22,8 +22,10 @@ -
-

 30 seconds of code

+
+

 30 seconds of code + Curated collection of useful Javascript snippets that you can understand in 30 seconds or less. +

From a80a62c56da7f00908ada432ab4e8d402065a1ee Mon Sep 17 00:00:00 2001 From: King Date: Tue, 19 Dec 2017 04:52:44 -0500 Subject: [PATCH 23/37] fix/update intializeArrayWithRange.md --- snippets/initializeArrayWithRange.md | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/snippets/initializeArrayWithRange.md b/snippets/initializeArrayWithRange.md index 75dbc8adf..8a58c1bbb 100644 --- a/snippets/initializeArrayWithRange.md +++ b/snippets/initializeArrayWithRange.md @@ -1,12 +1,13 @@ ### 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. 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] ``` From 8f69f4432fb373d3f3be075d47bf657749b0d2b0 Mon Sep 17 00:00:00 2001 From: King Date: Tue, 19 Dec 2017 05:00:49 -0500 Subject: [PATCH 24/37] fix up description --- snippets/initializeArrayWithRange.md | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/snippets/initializeArrayWithRange.md b/snippets/initializeArrayWithRange.md index 8a58c1bbb..c3ef5a0a0 100644 --- a/snippets/initializeArrayWithRange.md +++ b/snippets/initializeArrayWithRange.md @@ -2,7 +2,7 @@ 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 From ab971e7f4d7b71c4c9207b32ca103b68bd3e2898 Mon Sep 17 00:00:00 2001 From: Angelos Chalaris Date: Tue, 19 Dec 2017 12:01:29 +0200 Subject: [PATCH 25/37] Rebuild website --- docs/index.html | 2 +- static-parts/index-start.html | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/docs/index.html b/docs/index.html index d95229aa1..3e4e53b93 100644 --- a/docs/index.html +++ b/docs/index.html @@ -28,7 +28,7 @@
-
+
-
+

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.

+
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]
+

distinctValuesOfArray

Returns all the distinct values of an array.

Use ES6 Set and the ...rest operator to discard all duplicated values.

@@ -218,14 +229,22 @@ Recursively flatten each element that is an array.


dropElements

Removes elements in an array until the passed function returns true. Returns the remaining elements in the array.

-

Loop through the array, using Array.shift() to drop the first element of the array until the returned value from the function is true. +

Loop through the array, using Array.slice() to drop the first element of the array until the returned value from the function is true. Returns the remaining elements.

const dropElements = (arr, func) => {
-  while (arr.length > 0 && !func(arr[0])) arr.shift();
+  while (arr.length > 0 && !func(arr[0])) arr = arr.slice(1);
   return arr;
 };
 // dropElements([1, 2, 3, 4], n => n >= 3) -> [3,4]
+

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.

+
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) -> []
+

everyNth

Returns every nth element in an array.

Use Array.filter() to create a new array that contains every nth element of a given array.

@@ -278,12 +297,13 @@ Use Array.reduce() to create an object, where the keys are produced // initial([1,2,3]) -> [1,2]

initializeArrayWithRange

-

Initializes an array containing the numbers in the specified range.

-

Use Array(end-start) to create an array of the desired length, Array.map() to fill with the desired values in a range. +

Initializes an array containing the numbers in the specified range where start and end are inclusive.

+

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.

-
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]

initializeArrayWithValues

Initializes and fills an array with the specified values.

@@ -334,6 +354,7 @@ Omit the second argument, n, to get the first element of the array.

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)

const pull = (arr, ...args) => {
   let pulled = arr.filter((v, i) => !args.includes(v));
   arr.length = 0; pulled.forEach(v => arr.push(v));
@@ -342,6 +363,38 @@ Use Array.length = 0 to mutate the passed in array by resetting it'
 // pull(myArray, 'a', 'c');
 // console.log(myArray) -> [ 'b', 'b' ]
+

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.

+
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' ]
+
+

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

+
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' ]
+

remove

Removes elements from an array for which the given function returns false.

Use Array.filter() to find array elements that return truthy values and Array.reduce() to remove elements using Array.splice(). @@ -411,6 +464,7 @@ This method also works with strings.


without

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)

const without = (arr, ...args) => arr.filter(v => !args.includes(v));
 // without([2, 1, 2, 3], 1, 2) -> [3]
@@ -433,7 +487,7 @@ If lengths of the argument-arrays vary, undefined is used where no

Returns true if the bottom of the page is visible, false otherwise.

Use scrollY, scrollHeight and clientHeight to determine if the bottom of the page is visible.

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

currentURL

@@ -708,7 +762,7 @@ The GCD formula uses recursion.

Find the middle of the array, use Array.sort() to sort the values. Return the number at the midpoint if length is odd, otherwise the average of the two middle numbers.

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
@@ -842,6 +896,15 @@ Also if you give it a special key (childIndicator) it will search d
 
const objectToPairs = obj => Object.keys(obj).map(k => [k, obj[k]]);
 // objectToPairs({a: 1, b: 2}) -> [['a',1],['b',2]])
 

+

select

+

Retrieve a property that indicated by the selector from object.

+

If property not exists returns undefined.

+
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'
+

shallowClone

Creates a shallow clone of an object.

Use Object.assign() and an empty object ({}) to create a shallow clone of the original.

@@ -890,8 +953,7 @@ Omit the lowerRest parameter to keep the rest of the string intact,

countVowels

Retuns number of vowels in provided string.

Use a regular expression to count number of vowels (A, E, I, O, U) in a string.

-
const countVowels = str =>
-  return (str.match(/[aeiou]/ig) || []).length;
+
const countVowels = str => (str.match(/[aeiou]/ig) || []).length;
 // countVowels('foobar') -> 3
 // countVowels('gym') -> 0
 

@@ -914,9 +976,9 @@ Omit the second argument to use a default separator of _.

reverseString

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('').

-
const reverseString = str => [...str].reverse().join('');
+
const reverseString = str => str.split('').reverse().join('');
 // reverseString('foobar') -> 'raboof'

sortCharactersInString

diff --git a/tag_database b/tag_database index 89d7bc547..2d675024c 100644 --- a/tag_database +++ b/tag_database @@ -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