diff --git a/README.md b/README.md index 0f5be216b..eedc27383 100644 --- a/README.md +++ b/README.md @@ -142,6 +142,7 @@ average(1, 2, 3); * [`intersectionWith`](#intersectionwith) * [`isSorted`](#issorted) * [`join`](#join) +* [`JSONtoCSV`](#jsontocsv-) * [`last`](#last) * [`longestItem`](#longestitem) * [`mapObject`](#mapobject-) @@ -856,8 +857,8 @@ any([0, 0, 1, 0]); // true Converts a 2D array to a comma-separated values (CSV) string. -Use `Array.map()` and `String.join(delimiter)` to combine individual 1D arrays (rows) into strings. -Use `String.join('\n')` to combine all rows into a CSV string, separating each row with a newline. +Use `Array.map()` and `Array.join(delimiter)` to combine individual 1D arrays (rows) into strings. +Use `Array.join('\n')` to combine all rows into a CSV string, separating each row with a newline. Omit the second argument, `delimiter`, to use a default delimiter of `,`. ```js @@ -1734,6 +1735,41 @@ join(['pen', 'pineapple', 'apple', 'pen']); // "pen,pineapple,apple,pen"
[⬆ Back to top](#table-of-contents) +### JSONtoCSV ![advanced](/advanced.svg) + +Converts an array of objects to a comma-separated values (CSV) string that contains only the `columns` specified. + +Use `Array.join(demiliter)` to combine all the names in `columns` to create the first row. +Use `Array.map()` and `Array.reduce()` to create a row for each object, substituting non-existent values with empty strings and only mapping values in `columns`. +Use `Array.join('\n')` to combine all rows into a string. +Omit the third argument, `delimiter`, to use a default delimiter of `,`. + +```js +const JSONtoCSV = (arr, columns, delimiter = ',') => + [ + columns.join(delimiter), + ...arr.map(obj => + columns.reduce( + (acc, key) => `${acc}${!acc.length ? '' : delimiter}"${!obj[key] ? '' : obj[key]}"`, + '' + ) + ) + ].join('\n'); +``` + +
+Examples + +```js +JSONtoCSV([{ a: 1, b: 2 }, { a: 3, b: 4, c: 5 }, { a: 6 }, { b: 7 }], ['a', 'b']); // 'a,b\n"1","2"\n"3","4"\n"6",""\n"","7"' +JSONtoCSV([{ a: 1, b: 2 }, { a: 3, b: 4, c: 5 }, { a: 6 }, { b: 7 }], ['a', 'b'], ';'); // 'a;b\n"1";"2"\n"3";"4"\n"6";""\n"";"7"' +``` + +
+ +
[⬆ Back to top](#table-of-contents) + + ### last Returns the last element in an array. diff --git a/docs/adapter.html b/docs/adapter.html index 7bca4f539..8edc11cc2 100644 --- a/docs/adapter.html +++ b/docs/adapter.html @@ -79,7 +79,7 @@ document.getElementById('doc-drawer-checkbox').checked = false; } }, false); - }

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Adapter

ary

Creates a function that accepts up to n arguments, ignoring any additional arguments.

Call the provided function, fn, with up to n arguments, using Array.slice(0,n) and the spread operator (...).

const ary = (fn, n) => (...args) => fn(...args.slice(0, n));
+      }
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Adapter
ary
Creates a function that accepts up to n arguments, ignoring any additional arguments.
Call the provided function, fn, with up to n arguments, using Array.slice(0,n) and the spread operator (...).
const ary = (fn, n) => (...args) => fn(...args.slice(0, n));
 
const firstTwoMax = ary(Math.max, 2);
 [[2, 6, 'a'], [8, 4, 6], [10]].map(x => firstTwoMax(...x)); // [6, 8, 10]
 
call
Given a key and a set of arguments, call them when given a context. Primarily useful in composition.
Use a closure to call a stored key with stored arguments.
const call = (key, ...args) => context => context[key](...args);
diff --git a/docs/array.html b/docs/array.html
index 823d0232b..39df8ddc4 100644
--- a/docs/array.html
+++ b/docs/array.html
@@ -79,13 +79,13 @@
             document.getElementById('doc-drawer-checkbox').checked = false;
           }
         }, false);
-      }
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Array
all
Returns true if the provided predicate function returns true for all elements in a collection, false otherwise.
Use Array.every() to test if all elements in the collection return true based on fn. Omit the second argument, fn, to use Boolean as a default.
const all = (arr, fn = Boolean) => arr.every(fn);
+      }
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Array
all
Returns true if the provided predicate function returns true for all elements in a collection, false otherwise.
Use Array.every() to test if all elements in the collection return true based on fn. Omit the second argument, fn, to use Boolean as a default.
const all = (arr, fn = Boolean) => arr.every(fn);
 
all([4, 2, 3], x => x > 1); // true
 all([1, 2, 3]); // true
 
any
Returns true if the provided predicate function returns true for at least one element in a collection, false otherwise.
Use Array.some() to test if any elements in the collection return true based on fn. Omit the second argument, fn, to use Boolean as a default.
const any = (arr, fn = Boolean) => arr.some(fn);
 
any([0, 1, 2, 0], x => x >= 2); // true
 any([0, 0, 1, 0]); // true
-
arrayToCSV
Converts a 2D array to a comma-separated values (CSV) string.
Use Array.map() and String.join(delimiter) to combine individual 1D arrays (rows) into strings. Use String.join('\n') to combine all rows into a CSV string, separating each row with a newline. Omit the second argument, delimiter, to use a default delimiter of ,.
const arrayToCSV = (arr, delimiter = ',') => arr.map(v => v.join(delimiter)).join('\n');
+
arrayToCSV
Converts a 2D array to a comma-separated values (CSV) string.
Use Array.map() and Array.join(delimiter) to combine individual 1D arrays (rows) into strings. Use Array.join('\n') to combine all rows into a CSV string, separating each row with a newline. Omit the second argument, delimiter, to use a default delimiter of ,.
const arrayToCSV = (arr, delimiter = ',') => arr.map(v => v.join(delimiter)).join('\n');
 
arrayToCSV([['a', 'b'], ['c', 'd']]); // 'a,b\nc,d'
 arrayToCSV([['a', 'b'], ['c', 'd']], ';'); // 'a;b\nc;d'
 
bifurcate
Splits values into two groups. If an element in filter is truthy, the corresponding element in the collection belongs to the first group; otherwise, it belongs to the second group.
Use Array.reduce() and Array.push() to add elements to groups, based on filter.
const bifurcate = (arr, filter) =>
@@ -242,6 +242,18 @@
 
join(['pen', 'pineapple', 'apple', 'pen'], ',', '&'); // "pen,pineapple,apple&pen"
 join(['pen', 'pineapple', 'apple', 'pen'], ','); // "pen,pineapple,apple,pen"
 join(['pen', 'pineapple', 'apple', 'pen']); // "pen,pineapple,apple,pen"
+
JSONtoCSVadvanced
Converts an array of objects to a comma-separated values (CSV) string that contains only the columns specified.
Use Array.join(demiliter) to combine all the names in columns to create the first row. Use Array.map() and Array.reduce() to create a row for each object, substituting non-existent values with empty strings and only mapping values in columns. Use Array.join('\n') to combine all rows into a string. Omit the third argument, delimiter, to use a default delimiter of ,.
const JSONtoCSV = (arr, columns, delimiter = ',') =>
+  [
+    columns.join(delimiter),
+    ...arr.map(obj =>
+      columns.reduce(
+        (acc, key) => `${acc}${!acc.length ? '' : delimiter}"${!obj[key] ? '' : obj[key]}"`,
+        ''
+      )
+    )
+  ].join('\n');
+
JSONtoCSV([{ a: 1, b: 2 }, { a: 3, b: 4, c: 5 }, { a: 6 }, { b: 7 }], ['a', 'b']); // 'a,b\n"1","2"\n"3","4"\n"6",""\n"","7"'
+JSONtoCSV([{ a: 1, b: 2 }, { a: 3, b: 4, c: 5 }, { a: 6 }, { b: 7 }], ['a', 'b'], ';'); // 'a;b\n"1";"2"\n"3";"4"\n"6";""\n"";"7"'
 
last
Returns the last element in an array.
Use arr.length - 1 to compute the index of the last element of the given array and returning it.
const last = arr => arr[arr.length - 1];
 
last([1, 2, 3]); // 3
 
longestItem
Takes any number of iterable objects or objects with a length property and returns the longest one.
Use Array.sort() to sort all arguments by length, return the first (longest) one.
const longestItem = (...vals) => [...vals].sort((a, b) => b.length - a.length)[0];
diff --git a/docs/browser.html b/docs/browser.html
index b3e2d2c04..fdc6451fa 100644
--- a/docs/browser.html
+++ b/docs/browser.html
@@ -79,7 +79,7 @@
             document.getElementById('doc-drawer-checkbox').checked = false;
           }
         }, false);
-      }
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Browser
arrayToHtmlList
Converts the given array elements into <li> tags and appends them to the list of the given id.
Use Array.map(), document.querySelector(), and an anonymous inner closure to create a list of html tags.
const arrayToHtmlList = (arr, listID) =>
+      }
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Browser
arrayToHtmlList
Converts the given array elements into <li> tags and appends them to the list of the given id.
Use Array.map(), document.querySelector(), and an anonymous inner closure to create a list of html tags.
const arrayToHtmlList = (arr, listID) =>
   (el => (
     (el = document.querySelector('#' + listID)),
     (el.innerHTML += arr.map(item => `<li>${item}</li>`).join(''))
diff --git a/docs/date.html b/docs/date.html
index c49b7461b..2bc0e5fef 100644
--- a/docs/date.html
+++ b/docs/date.html
@@ -79,7 +79,7 @@
             document.getElementById('doc-drawer-checkbox').checked = false;
           }
         }, false);
-      }
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Date
formatDuration
Returns the human readable format of the given number of milliseconds.
Divide ms with the appropriate values to obtain the appropriate values for day, hour, minute, second and millisecond. Use Object.entries() with Array.filter() to keep only non-zero values. Use Array.map() to create the string for each value, pluralizing appropriately. Use String.join(', ') to combine the values into a string.
const formatDuration = ms => {
+      }
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Date
formatDuration
Returns the human readable format of the given number of milliseconds.
Divide ms with the appropriate values to obtain the appropriate values for day, hour, minute, second and millisecond. Use Object.entries() with Array.filter() to keep only non-zero values. Use Array.map() to create the string for each value, pluralizing appropriately. Use String.join(', ') to combine the values into a string.
const formatDuration = ms => {
   if (ms < 0) ms = -ms;
   const time = {
     day: Math.floor(ms / 86400000),
diff --git a/docs/function.html b/docs/function.html
index ea5e9657d..9dedc6689 100644
--- a/docs/function.html
+++ b/docs/function.html
@@ -79,7 +79,7 @@
             document.getElementById('doc-drawer-checkbox').checked = false;
           }
         }, false);
-      }
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Function
attempt
Attempts to invoke a function with the provided arguments, returning either the result or the caught error object.
Use a try... catch block to return either the result of the function or an appropriate error.
const attempt = (fn, ...args) => {
+      }
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Function
attempt
Attempts to invoke a function with the provided arguments, returning either the result or the caught error object.
Use a try... catch block to return either the result of the function or an appropriate error.
const attempt = (fn, ...args) => {
   try {
     return fn(...args);
   } catch (e) {
diff --git a/docs/math.html b/docs/math.html
index e201590a6..533025b41 100644
--- a/docs/math.html
+++ b/docs/math.html
@@ -79,7 +79,7 @@
             document.getElementById('doc-drawer-checkbox').checked = false;
           }
         }, false);
-      }
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Math
approximatelyEqual
Checks if two numbers are approximately equal to each other.
Use Math.abs() to compare the absolute difference of the two values to epsilon. Omit the third parameter, epsilon, to use a default value of 0.001.
const approximatelyEqual = (v1, v2, epsilon = 0.001) => Math.abs(v1 - v2) < epsilon;
+      }
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Math
approximatelyEqual
Checks if two numbers are approximately equal to each other.
Use Math.abs() to compare the absolute difference of the two values to epsilon. Omit the third parameter, epsilon, to use a default value of 0.001.
const approximatelyEqual = (v1, v2, epsilon = 0.001) => Math.abs(v1 - v2) < epsilon;
 
approximatelyEqual(Math.PI / 2.0, 1.5708); // true
 
average
Returns the average of two or more numbers.
Use Array.reduce() to add each value to an accumulator, initialized with a value of 0, divide by the length of the array.
const average = (...nums) => [...nums].reduce((acc, val) => acc + val, 0) / nums.length;
 
average(...[1, 2, 3]); // 2
diff --git a/docs/node.html b/docs/node.html
index 44d7f146d..c6cf3c069 100644
--- a/docs/node.html
+++ b/docs/node.html
@@ -79,7 +79,7 @@
             document.getElementById('doc-drawer-checkbox').checked = false;
           }
         }, false);
-      }
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Node
atob
Decodes a string of data which has been encoded using base-64 encoding.
Create a Buffer for the given string with base-64 encoding and use Buffer.toString('binary') to return the decoded string.
const atob = str => new Buffer(str, 'base64').toString('binary');
+      }
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Node
atob
Decodes a string of data which has been encoded using base-64 encoding.
Create a Buffer for the given string with base-64 encoding and use Buffer.toString('binary') to return the decoded string.
const atob = str => new Buffer(str, 'base64').toString('binary');
 
atob('Zm9vYmFy'); // 'foobar'
 
btoa
Creates a base-64 encoded ASCII string from a String object in which each character in the string is treated as a byte of binary data.
Create a Buffer for the given string with binary encoding and use Buffer.toString('base64') to return the encoded string.
const btoa = str => new Buffer(str, 'binary').toString('base64');
 
btoa('foobar'); // 'Zm9vYmFy'
diff --git a/docs/object.html b/docs/object.html
index 34eef1874..168a32ded 100644
--- a/docs/object.html
+++ b/docs/object.html
@@ -79,7 +79,7 @@
             document.getElementById('doc-drawer-checkbox').checked = false;
           }
         }, false);
-      }
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Object
bindAll
Binds methods of an object to the object itself, overwriting the existing method.
Use Array.forEach() to return a function that uses Function.apply() to apply the given context (obj) to fn for each function specified.
const bindAll = (obj, ...fns) =>
+      }
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Object
bindAll
Binds methods of an object to the object itself, overwriting the existing method.
Use Array.forEach() to return a function that uses Function.apply() to apply the given context (obj) to fn for each function specified.
const bindAll = (obj, ...fns) =>
   fns.forEach(
     fn => (
       (f = obj[fn]),
diff --git a/docs/string.html b/docs/string.html
index 79acbb2b8..30cbc4737 100644
--- a/docs/string.html
+++ b/docs/string.html
@@ -79,7 +79,7 @@
             document.getElementById('doc-drawer-checkbox').checked = false;
           }
         }, false);
-      }
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String
byteSize
Returns the length of a string in bytes.
Convert a given string to a Blob Object and find its size.
const byteSize = str => new Blob([str]).size;
+      }
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String
byteSize
Returns the length of a string in bytes.
Convert a given string to a Blob Object and find its size.
const byteSize = str => new Blob([str]).size;
 
byteSize('😀'); // 4
 byteSize('Hello World'); // 11
 
capitalize
Capitalizes the first letter of a string.
Use array destructuring and String.toUpperCase() to capitalize first letter, ...rest to get array of characters after first letter and then Array.join('') to make it a string again. Omit the lowerRest parameter to keep the rest of the string intact, or set it to true to convert to lowercase.
const capitalize = ([first, ...rest], lowerRest = false) =>
diff --git a/docs/type.html b/docs/type.html
index 7d661ac41..e2b85c9bf 100644
--- a/docs/type.html
+++ b/docs/type.html
@@ -79,7 +79,7 @@
             document.getElementById('doc-drawer-checkbox').checked = false;
           }
         }, false);
-      }
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Type
getType
Returns the native type of a value.
Returns lowercased constructor name of value, "undefined" or "null" if value is undefined or null.
const getType = v =>
+      }
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Type
getType
Returns the native type of a value.
Returns lowercased constructor name of value, "undefined" or "null" if value is undefined or null.
const getType = v =>
   v === undefined ? 'undefined' : v === null ? 'null' : v.constructor.name.toLowerCase();
 
getType(new Set([1, 2, 3])); // 'set'
 
is
Checks if the provided value is of the specified type.
Ensure the value is not undefined or null using Array.includes(), and compare the constructor property on the value with type to check if the provided value is of the specified type.
const is = (type, val) => ![, null].includes(val) && val.constructor === type;
diff --git a/docs/utility.html b/docs/utility.html
index 63d301600..f6039dc60 100644
--- a/docs/utility.html
+++ b/docs/utility.html
@@ -79,7 +79,7 @@
             document.getElementById('doc-drawer-checkbox').checked = false;
           }
         }, false);
-      }
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Utility
castArray
Casts the provided value as an array if it's not one.
Use Array.isArray() to determine if val is an array and return it as-is or encapsulated in an array accordingly.
const castArray = val => (Array.isArray(val) ? val : [val]);
+      }
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Utility
castArray
Casts the provided value as an array if it's not one.
Use Array.isArray() to determine if val is an array and return it as-is or encapsulated in an array accordingly.
const castArray = val => (Array.isArray(val) ? val : [val]);
 
castArray('foo'); // ['foo']
 castArray([1]); // [1]
 
cloneRegExp
Clones a regular expression.
Use new RegExp(), RegExp.source and RegExp.flags to clone the given regular expression.
const cloneRegExp = regExp => new RegExp(regExp.source, regExp.flags);