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3.2.19 • Public • Published

An iterable is a sequence of values.
📦 Node.js, 🌐 Web, 📜 Files, 📰 Docs, 📘 Wiki.

This is a collection of functions for operating upon iterables. Assumption here is that an iterable can only be iterated over once. Methods which require multiple iterations preserve old values in a backup array using toMany. Many methods accept both compare and map functions, and in some cases using only a map function enables faster comparision (like unique). I borrowed a lot of ideas from Haskell, Elm, Python, Basic, Lodash, and other NPM packages. These are mentioned in references of each method.

This package is available in Node.js and Web formats. To use it on the web, simply use the extra_iterable global variable after loading with a <script> tag from the jsDelivr CDN.

Stability: Experimental.

const xiterable = require('extra-iterable');
// import * as xiterable from "extra-iterable";
// import * as xiterable from "https://unpkg.com/extra-iterable/index.mjs"; (deno)

var x = [2, 4, 6, 8];
xiterable.get(x, 1);
// → 4

var x = [1, 2, 3, 4];
[...xiterable.swap(x, 0, 1)];
// → [ 2, 1, 3, 4 ]

var x = [1, 2, 3];
[...xiterable.cycle(x, 0, 4)];
// → [1, 2, 3, 1]

var x = [1, 2, 3, 4];
xiterable.reduce(x, (acc, v) => acc+v);
// → 10


Property Description
is Check if value is an iterable.
isIterator Check if value is an iterator.
isList Check if value is a list (iterable & !string).
iterator Get iterator of an iterable.
keys List all indices.
values List all values.
entries List all index-value pairs.
from Convert an iterable-like to iterable.
fromIterator Convert an iterator to iterable.
fromRange Generate iterable from given number range.
fromInvocation Generate iterable from repeated function invocation.
fromApplication Generate iterable from repeated function application.
isOnce Check if an iterable can iterated only once.
isMany Check if an iterable can be iterated many times.
toMany Convert a once-like iterable to many.
toInvokable Generate a function that iterates over values upon invocation.
isEmpty Check if an iterable is empty.
length Find the length of an iterable.
compare Compare two iterables.
isEqual Check if two iterables are equal.
index Get zero-based index for element in iterable.
indexRange Get index range for part of iterable.
get Get value at index.
getAll Get values at indices.
getPath Get value at path in a nested iterable.
hasPath Check if nested iterable has a path.
set Set value at index.
swap Exchange two values.
remove Remove value at index.
count Count values which satisfy a test.
countAs Count occurrences of values.
min Find smallest value.
max Find largest value.
range Find smallest and largest values.
minEntry Find smallest entry.
maxEntry Find largest entry.
rangeEntries Find smallest and largest entries.
slice Get part of an iterable.
head Get first value.
last Get last value.
tail Get values except first.
init Get values except last.
left Get values from left.
right Get values from right.
middle Get values from middle.
take Keep first n values only.
takeRight Keep last n values only.
takeWhile Keep values from left, while a test passes.
takeWhileRight Keep values from right, while a test passes.
drop Discard first n values only.
dropRight Discard last n values only.
dropWhile Discard values from left, while a test passes.
dropWhileRight Discard values from right, while a test passes.
includes Check if iterable has a value.
indexOf Find first index of a value.
lastIndexOf Find last index of a value.
find Find first value passing a test.
findRight Find last value passing a test.
scanWhile Scan from left, while a test passes.
scanWhileRight Scan from right, while a test passes.
scanUntil Scan from left, until a test passes.
scanUntilRight Scan from right, until a test passes.
search Find index of first value passing a test.
searchRight Find index of last value passing a test.
searchAll Find indices of values passing a test.
searchValue Find first index of a value.
searchValueRight Find last index of a value.
searchValueAll Find indices of a value.
searchInfix Find first index of an infix.
searchInfixRight Find last index of an infix.
searchInfixAll Find indices of an infix.
searchSubsequence Find first index of a subsequence.
hasValue Check if iterable has a value.
hasPrefix Check if iterable starts with a prefix.
hasSuffix Check if iterable ends with a suffix.
hasInfix Check if iterable contains an infix.
hasSubsequence Check if iterable has a subsequence.
forEach Call a function for each value.
some Check if any value satisfies a test.
every Check if all values satisfy a test.
map Transform values of an iterable.
reduce Reduce values of iterable to a single value.
filter Keep the values which pass a test.
filterAt Keep the values at given indices.
reject Discard the values which pass a test.
rejectAt Discard the values at given indices.
accumulate Produce accumulating values.
flat Flatten nested iterable to given depth.
flatMap Flatten nested iterable, based on map function.
zip Combine values from iterables.
fill Fill with given value.
push Add values to the end.
unshift Add values to the start.
copy Copy part of iterable to another.
copyWithin Copy part of iterable within.
moveWithin Move part of iterable within.
splice Remove or replaces existing values.
split Break iterable considering test as separator.
splitAt Break iterable considering indices as separator.
cut Break iterable when test passes.
cutRight Break iterable after test passes.
cutAt Break iterable at given indices.
cutAtRight Break iterable after given indices.
group Keep similar values together and in order.
partition Segregate values by test result.
partitionAs Segregate values by similarity.
chunk Break iterable into chunks of given size.
cycle Obtain values that cycle through an iterable.
repeat Repeat an iterable given times.
reverse Reverse the values.
rotate Rotate values in iterable.
intersperse Place a separator between every value.
interpolate Estimate new values between existing ones.
intermix Place values of an iterable between another.
interleave Place values from iterables alternately.
concat Append values from iterables.
merge Merge values from sorted iterables.
join Join values together into a string.
isUnique Check if there are no duplicate values.
isDisjoint Checks if arrays have no value in common.
unique Remove duplicate values.
union Obtain values present in any iterable.
intersection Obtain values present in both iterables.
difference Obtain values not present in another iterable.
symmetricDifference Obtain values not present in both iterables.
cartesianProduct List cartesian product of iterables.

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