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Avoid confusing prototype methods for static methods

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Correct: `Array.from()` (it’s a static method)
Incorrect: `Array.join()` (doesn’t exist; it’s a prototype method)

This patch uses the common `#` syntax to denote `.prototype.`.
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Mathias Bynens
2018-09-28 15:12:52 -04:00
parent 242a18e0a8
commit 8ee50178f3
194 changed files with 545 additions and 545 deletions
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@ -5,7 +5,7 @@
"type": "snippet",
"attributes": {
"fileName": "binarySearch.md",
"text": "Use recursion. Similar to `Array.indexOf()` that finds the index of a value within an array.\nThe difference being this operation only works with sorted arrays which offers a major performance boost due to it's logarithmic nature when compared to a linear search or `Array.indexOf()`.\n\nSearch a sorted array by repeatedly dividing the search interval in half.\nBegin with an interval covering the whole array.\nIf the value of the search is less than the item in the middle of the interval, recurse into the lower half. Otherwise recurse into the upper half.\nRepeatedly recurse until the value is found which is the mid or you've recursed to a point that is greater than the length which means the value doesn't exist and return `-1`.",
"text": "Use recursion. Similar to `Array.prototype.indexOf()` that finds the index of a value within an array.\nThe difference being this operation only works with sorted arrays which offers a major performance boost due to it's logarithmic nature when compared to a linear search or `Array.prototype.indexOf()`.\n\nSearch a sorted array by repeatedly dividing the search interval in half.\nBegin with an interval covering the whole array.\nIf the value of the search is less than the item in the middle of the interval, recurse into the lower half. Otherwise recurse into the upper half.\nRepeatedly recurse until the value is found which is the mid or you've recursed to a point that is greater than the length which means the value doesn't exist and return `-1`.",
"codeBlocks": [
"const binarySearch = (arr, val, start = 0, end = arr.length - 1) => {\n if (start > end) return -1;\n const mid = Math.floor((start + end) / 2);\n if (arr[mid] > val) return binarySearch(arr, val, start, mid - 1);\n if (arr[mid] < val) return binarySearch(arr, val, mid + 1, end);\n return mid;\n};",
"binarySearch([1, 4, 6, 7, 12, 13, 15, 18, 19, 20, 22, 24], 6); // 2\nbinarySearch([1, 4, 6, 7, 12, 13, 15, 18, 19, 20, 22, 24], 21); // -1"
@ -73,7 +73,7 @@
"type": "snippet",
"attributes": {
"fileName": "factors.md",
"text": "Returns the array of factors of the given `num`. \nIf the second argument is set to `true` returns only the prime factors of `num`.\nIf `num` is `1` or `0` returns an empty array.\nIf `num` is less than `0` returns all the factors of `-int` together with their additive inverses.\n\nUse `Array.from()`, `Array.map()` and `Array.filter()` to find all the factors of `num`.\nIf given `num` is negative, use `Array.reduce()` to add the additive inverses to the array.\nReturn all results if `primes` is `false`, else determine and return only the prime factors using `isPrime` and `Array.filter()`.\nOmit the second argument, `primes`, to return prime and non-prime factors by default.\n\n**Note**:- _Negative numbers are not considered prime._",
"text": "Returns the array of factors of the given `num`. \nIf the second argument is set to `true` returns only the prime factors of `num`.\nIf `num` is `1` or `0` returns an empty array.\nIf `num` is less than `0` returns all the factors of `-int` together with their additive inverses.\n\nUse `Array.from()`, `Array.prototype.map()` and `Array.prototype.filter()` to find all the factors of `num`.\nIf given `num` is negative, use `Array.prototype.reduce()` to add the additive inverses to the array.\nReturn all results if `primes` is `false`, else determine and return only the prime factors using `isPrime` and `Array.prototype.filter()`.\nOmit the second argument, `primes`, to return prime and non-prime factors by default.\n\n**Note**:- _Negative numbers are not considered prime._",
"codeBlocks": [
"const factors = (num, primes = false) => {\n const isPrime = num => {\n const boundary = Math.floor(Math.sqrt(num));\n for (var i = 2; i <= boundary; i++) if (num % i === 0) return false;\n return num >= 2;\n };\n const isNeg = num < 0;\n num = isNeg ? -num : num;\n let array = Array.from({ length: num - 1 })\n .map((val, i) => (num % (i + 2) === 0 ? i + 2 : false))\n .filter(val => val);\n if (isNeg)\n array = array.reduce((acc, val) => {\n acc.push(val);\n acc.push(-val);\n return acc;\n }, []);\n return primes ? array.filter(isPrime) : array;\n};",
"factors(12); // [2,3,4,6,12]\nfactors(12, true); // [2,3]\nfactors(-12); // [2, -2, 3, -3, 4, -4, 6, -6, 12, -12]\nfactors(-12, true); // [2,3]"
@ -107,7 +107,7 @@
"type": "snippet",
"attributes": {
"fileName": "fibonacciUntilNum.md",
"text": "Generates an array, containing the Fibonacci sequence, up until the nth term.\n\nCreate an empty array of the specific length, initializing the first two values (`0` and `1`).\nUse `Array.reduce()` to add values into the array, using the sum of the last two values, except for the first two.\nUses a mathematical formula to calculate the length of the array required.",
"text": "Generates an array, containing the Fibonacci sequence, up until the nth term.\n\nCreate an empty array of the specific length, initializing the first two values (`0` and `1`).\nUse `Array.prototype.reduce()` to add values into the array, using the sum of the last two values, except for the first two.\nUses a mathematical formula to calculate the length of the array required.",
"codeBlocks": [
"const fibonacciUntilNum = num => {\n let n = Math.ceil(Math.log(num * Math.sqrt(5) + 1 / 2) / Math.log((Math.sqrt(5) + 1) / 2));\n return Array.from({ length: n }).reduce(\n (acc, val, i) => acc.concat(i > 1 ? acc[i - 1] + acc[i - 2] : i),\n []\n );\n};",
"fibonacciUntilNum(10); // [ 0, 1, 1, 2, 3, 5, 8 ]"
@ -260,7 +260,7 @@
"type": "snippet",
"attributes": {
"fileName": "quickSort.md",
"text": "QuickSort an Array (ascending sort by default).\n\nUse recursion. \nUse `Array.filter` and spread operator (`...`) to create an array that all elements with values less than the pivot come before the pivot, and all elements with values greater than the pivot come after it. \nIf the parameter `desc` is truthy, return array sorts in descending order.",
"text": "QuickSort an Array (ascending sort by default).\n\nUse recursion. \nUse `Array.prototype.filter` and spread operator (`...`) to create an array that all elements with values less than the pivot come before the pivot, and all elements with values greater than the pivot come after it. \nIf the parameter `desc` is truthy, return array sorts in descending order.",
"codeBlocks": [
"const quickSort = ([n, ...nums], desc) =>\n isNaN(n)\n ? []\n : [\n ...quickSort(nums.filter(v => (desc ? v > n : v <= n)), desc),\n n,\n ...quickSort(nums.filter(v => (!desc ? v > n : v <= n)), desc)\n ];",
"quickSort([4, 1, 3, 2]); // [1,2,3,4]\nquickSort([4, 1, 3, 2], true); // [4,3,2,1]"
@ -330,7 +330,7 @@
"type": "snippet",
"attributes": {
"fileName": "removeVowels.md",
"text": "Returns all the vowels in a `str` replaced by `repl`.\n\nUse `String.replace()` with a regexp to replace all vowels in `str`.\nOmot `repl` to use a default value of `''`.",
"text": "Returns all the vowels in a `str` replaced by `repl`.\n\nUse `String.prototype.replace()` with a regexp to replace all vowels in `str`.\nOmot `repl` to use a default value of `''`.",
"codeBlocks": [
"const removeVowels = (str, repl = '') => str.replace(/[aeiou]/gi, repl);",
"removeVowels(\"foobAr\"); // \"fbr\"\nremoveVowels(\"foobAr\",\"*\"); // \"f**b*r\""
@ -347,7 +347,7 @@
"type": "snippet",
"attributes": {
"fileName": "solveRPN.md",
"text": "Solves the given mathematical expression in [reverse polish notation](https://en.wikipedia.org/wiki/Reverse_Polish_notation).\nThrows appropriate errors if there are unrecognized symbols or the expression is wrong. The valid operators are :- `+`,`-`,`*`,`/`,`^`,`**` (`^`&`**` are the exponential symbols and are same). This snippet does not supports any unary operators.\n\nUse a dictionary, `OPERATORS` to specify each operator's matching mathematical operation.\nUse `String.replace()` with a regular expression to replace `^` with `**`, `String.split()` to tokenize the string and `Array.filter()` to remove empty tokens.\nUse `Array.forEach()` to parse each `symbol`, evaluate it as a numeric value or operator and solve the mathematical expression.\nNumeric values are converted to floating point numbers and pushed to a `stack`, while operators are evaluated using the `OPERATORS` dictionary and pop elements from the `stack` to apply operations.",
"text": "Solves the given mathematical expression in [reverse polish notation](https://en.wikipedia.org/wiki/Reverse_Polish_notation).\nThrows appropriate errors if there are unrecognized symbols or the expression is wrong. The valid operators are :- `+`,`-`,`*`,`/`,`^`,`**` (`^`&`**` are the exponential symbols and are same). This snippet does not supports any unary operators.\n\nUse a dictionary, `OPERATORS` to specify each operator's matching mathematical operation.\nUse `String.prototype.replace()` with a regular expression to replace `^` with `**`, `String.prototype.split()` to tokenize the string and `Array.prototype.filter()` to remove empty tokens.\nUse `Array.prototype.forEach()` to parse each `symbol`, evaluate it as a numeric value or operator and solve the mathematical expression.\nNumeric values are converted to floating point numbers and pushed to a `stack`, while operators are evaluated using the `OPERATORS` dictionary and pop elements from the `stack` to apply operations.",
"codeBlocks": [
"const solveRPN = rpn => {\n const OPERATORS = {\n '*': (a, b) => a * b,\n '+': (a, b) => a + b,\n '-': (a, b) => a - b,\n '/': (a, b) => a / b,\n '**': (a, b) => a ** b\n };\n const [stack, solve] = [\n [],\n rpn\n .replace(/\\^/g, '**')\n .split(/\\s+/g)\n .filter(el => !/\\s+/.test(el) && el !== '')\n ];\n solve.forEach(symbol => {\n if (!isNaN(parseFloat(symbol)) && isFinite(symbol)) {\n stack.push(symbol);\n } else if (Object.keys(OPERATORS).includes(symbol)) {\n const [a, b] = [stack.pop(), stack.pop()];\n stack.push(OPERATORS[symbol](parseFloat(b), parseFloat(a)));\n } else {\n throw `${symbol} is not a recognized symbol`;\n }\n });\n if (stack.length === 1) return stack.pop();\n else throw `${rpn} is not a proper RPN. Please check it and try again`;\n};",
"solveRPN('15 7 1 1 + - / 3 * 2 1 1 + + -'); // 5\nsolveRPN('2 3 ^'); // 8"