Module @prelude/generator

Generator module

A TypeScript library for working with iterables and generators, providing a rich set of utility functions for functional programming patterns.

Installation

npm i -E @prelude/generator

Usage

import * as G from '@prelude/generator'

console.log(G.pipe(
  G.charRange('a', 'c'),
  G.cycle,
  G.take(10),
  G.array
))
// [
//   'a', 'b', 'c', 'a',
//   'b', 'c', 'a', 'b',
//   'c', 'a'
// ]

API Reference

Functions

append - Creates a generator that yields all values from the source iterable followed by all values from appendValues.
areUnique - Checks if all elements in the iterable are unique according to their values or a derived key.
array - Converts an iterable to an array.
at - Retrieves the element at the specified index in an iterable.
batch - Creates a generator that yields arrays of values from the source iterable, grouped into batches of specified size.
bigproduct - Multiplies all numeric values in an iterable using BigInt for precise large number arithmetic.
bigsum - Sums all numeric values in an iterable using BigInt for precise large number arithmetic.
cartesianProduct - Creates a generator that yields all possible combinations of elements from multiple iterables.
charRange - Creates a generator that yields characters in a range from start to end character.
combinations - Creates a generator that yields all possible combinations of a specific length from an iterable.
compact - Creates a generator that yields all non-nullish values from the source iterable.
composites - Creates a generator that yields composite numbers (non-prime numbers greater than 1).
concat - Creates a generator that yields all values from multiple iterables in sequence.
consume - Exhausts an iterable by iterating through all its values without returning anything.
count - Returns the number of elements in an iterable.
cycle - Creates a generator that yields the elements of an iterable repeatedly, cycling through them indefinitely.
defined - Creates a generator that yields only the defined values from the source iterable.
diff - Creates a generator that yields elements from the first iterable that are not present in the second iterable.
every - Checks if all elements in an iterable satisfy a given predicate.
extend - Creates a generator that yields elements from the source followed by a repeating value until a specified length is reached.
extreme - Finds the extreme (min/max) value in an iterable based on a comparison function.
fibonacci - Creates a generator that yields the Fibonacci sequence.
filter - Creates a generator that yields only elements from an iterable that pass a predicate test.
findIndex - Returns the index of the first element in an iterable that satisfies a predicate.
find - Returns the first element in an iterable that satisfies a predicate, or throws if none found.
first - Returns the first element of an iterable, or throws if the iterable is empty.
flatMap - Creates a generator that maps each element using a function and flattens the result.
flatten - Creates a generator that flattens nested iterables into a single level.
fork - Creates multiple independent iterators from a single iterable source.
from - Creates a generator from various input types.
generator - Creates a stateful generator function from an initialization function.
groupMap - Groups elements of an iterable by keys derived from a mapping function.
groupObject - Groups elements of an iterable by keys derived from a mapping function into an object.
group - Creates a generator that yields arrays of consecutive elements that share the same key.
interleave - Creates a generator that alternates values from multiple iterables.
joinStrings - Joins string values from an iterable with a separator.
last - Returns the last element of an iterable, or throws if the iterable is empty.
length - Returns the number of elements in an iterable.
lift - Converts a function that works on values to one that works on iterables.
map - Creates a generator that transforms each value in an iterable using a mapping function.
max - Returns the maximum value in an iterable according to a comparison function.
maybeFind - Returns the first element in an iterable that satisfies a predicate, or undefined if none found.
maybeFirst - Returns the first element of an iterable, or undefined if the iterable is empty.
maybeLast - Returns the last element of an iterable, or undefined if the iterable is empty.
maybeSingle - Returns the single element if the iterable contains exactly one element, or undefined otherwise.
memoized - Creates a generator that caches results of an input generator for reuse.
min - Returns the minimum value in an iterable according to a comparison function.
of - Creates a generator that yields the provided values.
pair - Creates a generator that yields pairs of adjacent elements from an iterable.
permutations - Creates a generator that yields all possible arrangements of elements from an iterable.
pipe - Passes a value through a series of transformations.
pipe0 - Creates a pipeline of transformations to be applied to a value later.
prelude - Exports helpers for integrating with @prelude libraries.
prepend - Creates a generator that yields values from prependValues followed by all values from the source iterable.
primeFactors - Creates a generator that yields all prime factors of a number.
primes - Creates a generator that yields prime numbers.
product - Multiplies all numeric values in an iterable.
properDivisors - Creates a generator that yields all proper divisors of a number.
range - Creates a generator that yields numbers in a sequence from start to end.
record - Converts an iterable of key-value pairs into a record object.
recursive - Creates a generator from a recursive function definition.
reduce - Applies a reducer function to each element in an iterable, resulting in a single output value.
reduce1 - Applies a reducer function to elements in a non-empty iterable, using the first element as the initial value.
repeat - Creates a generator that yields a value repeatedly.
retain - Creates a generator that keeps only elements that are present in both iterables.
reverse - Creates a generator that yields elements from an iterable in reverse order.
rotate - Creates a generator that rotates elements of an iterable by a specified offset.
single - Returns the single element if the iterable contains exactly one element, or throws otherwise.
skipWhile - Creates a generator that skips elements from an iterable as long as a predicate returns true.
skip - Creates a generator that skips a specified number of elements from the beginning of an iterable.
some - Checks if at least one element in an iterable satisfies a given predicate.
sort - Creates a generator that yields elements from an iterable in sorted order.
sortedDiff - Creates a generator that yields elements from the first sorted iterable that are not present in the second sorted iterable.
step - Creates a generator that yields every nth element from an iterable.
sum - Sums all numeric values in an iterable.
take - Creates a generator that yields a specified number of elements from the beginning of an iterable.
tap - Creates a generator that applies a side-effect function to each element while yielding the original values.
unique - Creates a generator that yields only unique values from an iterable.
unsafeCombinations - Creates a generator that yields all possible combinations of a specific length from an array.
unsafePermutations - Creates a generator that yields all possible arrangements of elements from an array.
until - Creates a generator that yields elements from an iterable until a predicate returns true.
while - Creates a generator that yields elements from an iterable as long as a predicate returns true.
window - Creates a generator that yields sliding windows of elements from an iterable.
withIndex - Creates a generator that yields pairs of [index, value] for each element in an iterable.
yield - Creates a generator that yields a single value.
zipRecord - Creates a generator that combines elements from iterables into record objects using provided keys.
zip - Creates a generator that combines corresponding elements from multiple iterables.