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@effect-ts/system

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Effect-TS is a zero dependency set of libraries to write highly productive, purely functional TypeScript at scale.

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// ets_tracing: off /** * adapted from https://github.com/gcanti/fp-ts */ import "../../../Operator/index.mjs"; import { identity } from "../../../Function/core.mjs"; import { isSome, none, some } from "../../../Option/index.mjs"; import * as Tp from "../Tuple/index.mjs"; /** * Composes computations in sequence, using the return value of one computation to determine the next computation. * * @ets_data_first chain_ */ export function chain(f) { return ma => chain_(ma, f); } /** * Composes computations in sequence, using the return value of one computation to determine the next computation. */ export function chain_(fa, f) { let resLen = 0; const l = fa.length; const temp = new Array(l); for (let i = 0; i < l; i++) { const e = fa[i]; const arr = f(e); resLen += arr.length; temp[i] = arr; } const r = Array(resLen); let start = 0; for (let i = 0; i < l; i++) { const arr = temp[i]; const l = arr.length; for (let j = 0; j < l; j++) { r[j + start] = arr[j]; } start += l; } return r; } /** * Splits an array into length-`n` pieces. The last piece will be shorter if `n` does not evenly divide the length of * the array. Note that `split(n)([])` is `[]`, not `[[]]`. This is intentional, and is consistent with a recursive * definition of `split`; it satisfies the property that * * ```ts * split(n)(xs).concat(split(n)(ys)) == split(n)(xs.concat(ys))) * ``` * * whenever `n` evenly divides the length of `xs`. * * @ets_data_first split_ */ export function split(n) { return as => split_(as, n); } /** * Splits an array into length-`n` pieces. The last piece will be shorter if `n` does not evenly divide the length of * the array. Note that `split(n)([])` is `[]`, not `[[]]`. This is intentional, and is consistent with a recursive * definition of `split`; it satisfies the property that * * ```ts * split(n)(xs).concat(split(n)(ys)) == split(n)(xs.concat(ys))) * ``` * * whenever `n` evenly divides the length of `xs`. */ export function split_(as, n) { const f = chop(splitAt(n)); return as.length === 0 ? empty() : isOutOfBound(n - 1, as) ? [as] : f(as); } /** * Filter out optional values */ export function compact(fa) { return collect(x => x)(fa); } /** * Concatenate */ export function concat_(x, y) { const lenx = x.length; if (lenx === 0) { return y; } const leny = y.length; if (leny === 0) { return x; } const r = Array(lenx + leny); for (let i = 0; i < lenx; i++) { r[i] = x[i]; } for (let i = 0; i < leny; i++) { r[i + lenx] = y[i]; } return r; } /** * Concatenate * * @ets_data_first concat_ */ export function concat(y) { return x => concat_(x, y); } /** * Attaches an element to the front of an array, creating a new non empty array * * ```ts * assert.deepStrictEqual(prepend_(0, [1, 2, 3]), [0, 1, 2, 3]) * ``` */ export function prepend_(tail, head) { const len = tail.length; const r = Array(len + 1); for (let i = 0; i < len; i++) { r[i + 1] = tail[i]; } r[0] = head; return r; } /** * Attaches an element to the front of an array, creating a new non empty array * * @ets_data_first prepend_ */ export function prepend(head) { return tail => prepend_(tail, head); } /** * Drop a number of elements from the start of an array, creating a new array * * ```ts * assert.deepStrictEqual(drop(2)([1, 2, 3]), [3]) * ``` * * @ets_data_first drop_ */ export function drop(n) { return as => drop_(as, n); } /** * Drop a number of elements from the start of an array, creating a new array */ export function drop_(as, n) { return as.slice(n, as.length); } /** * Remove the longest initial subarray for which all element satisfy the specified predicate, creating a new array * * ```ts * assert.deepStrictEqual(dropWhile((n: number) => n % 2 === 1)([1, 3, 2, 4, 5]), [2, 4, 5]) * ``` * * @ets_data_first dropWhile_ */ export function dropWhile(predicate) { return as => dropWhile_(as, predicate); } /** * Remove the longest initial subarray for which all element satisfy the specified predicate, creating a new array * * ``` * assert.deepStrictEqual(dropWhile((n: number) => n % 2 === 1)([1, 3, 2, 4, 5]), [2, 4, 5]) * ``` */ export function dropWhile_(as, predicate) { const i = spanIndex_(as, predicate); const l = as.length; const rest = Array(l - i); for (let j = i; j < l; j++) { rest[j - i] = as[j]; } return rest; } /** * Drop a number of elements from the end of an array, creating a new array * * ``` * assert.deepStrictEqual(dropRight(2)([1, 2, 3, 4, 5]), [1, 2, 3]) * ``` * * @ets_data_first dropRight_ */ export function dropRight(n) { return as => dropRight_(as, n); } /** * Drop a number of elements from the end of an array, creating a new array * * ``` * assert.deepStrictEqual(dropRight(2)([1, 2, 3, 4, 5]), [1, 2, 3]) * ``` */ export function dropRight_(as, n) { return as.slice(0, as.length - n); } /** * An empty array */ export function empty() { return []; } export function filter(predicate) { return fa => fa.filter(predicate); } export function filter_(fa, predicate) { return fa.filter(predicate); } /** * Filters the array also passing element index * * @ets_data_first filterWithIndex_ */ export function filterWithIndex(predicate) { return nea => filterWithIndex_(nea, predicate); } /** * Filters the array also passing element index */ export function filterWithIndex_(nea, predicate) { return nea.filter((a, i) => predicate(i, a)); } /** * Filters the array also mapping the output * * @ets_data_first collect_ */ export const collect = f => fa => collect_(fa, f); /** * Filters the array also mapping the output */ export function collect_(fa, f) { return collectWithIndex_(fa, (_, a) => f(a)); } /** * Filters the array also mapping the output * * @ets_data_first collectWithIndex_ */ export function collectWithIndex(f) { return fa => collectWithIndex_(fa, f); } /** * Filters the array also mapping the output */ export function collectWithIndex_(fa, f) { const result = []; for (let i = 0; i < fa.length; i++) { const optionB = f(i, fa[i]); if (isSome(optionB)) { result.push(optionB.value); } } return result; } /** * Maps an array until `none` is returned */ export function collectWhile_(arr, f) { const result = []; for (let i = 0; i < arr.length; i++) { const o = f(arr[i]); if (isSome(o)) { result.push(o.value); } else { break; } } return result; } /** * Maps an array until `none` is returned * * @ets_data_first collectWhile_ */ export function collectWhile(f) { return arr => collectWhile_(arr, f); } export function find(predicate) { return as => find_(as, predicate); } export function find_(as, predicate) { return findWithIndex_(as, (_, a) => predicate(a)); } export function findWithIndex_(as, predicate) { const len = as.length; for (let i = 0; i < len; i++) { if (predicate(i, as[i])) { return some(as[i]); } } return none; } export function findWithIndex(predicate) { return as => findWithIndex_(as, predicate); } /** * Find the first index for which a predicate holds * * ``` * assert.deepStrictEqual(findIndex((n: number) => n === 2)([1, 2, 3]), some(1)) * assert.deepStrictEqual(findIndex((n: number) => n === 2)([]), none) * ``` * * @ets_data_first findIndex_ */ export function findIndex(predicate) { return as => findIndex_(as, predicate); } /** * Find the first index for which a predicate holds */ export function findIndex_(as, predicate) { const len = as.length; for (let i = 0; i < len; i++) { if (predicate(as[i])) { return some(i); } } return none; } export function findLast(predicate) { return as => findLast_(as, predicate); } export function findLast_(as, predicate) { const len = as.length; for (let i = len - 1; i >= 0; i--) { if (predicate(as[i])) { return some(as[i]); } } return none; } /** * Returns the index of the last element of the list which matches the predicate * * ```ts * interface X { * a: number * b: number * } * const xs: Array<X> = [{ a: 1, b: 0 }, { a: 1, b: 1 }] * assert.deepStrictEqual(findLastIndex((x: { a: number }) => x.a === 1)(xs), some(1)) * assert.deepStrictEqual(findLastIndex((x: { a: number }) => x.a === 4)(xs), none) * ``` * * @ets_data_first findLastIndex_ */ export function findLastIndex(predicate) { return as => findLastIndex_(as, predicate); } /** * Returns the index of the last element of the list which matches the predicate */ export function findLastIndex_(as, predicate) { const len = as.length; for (let i = len - 1; i >= 0; i--) { if (predicate(as[i])) { return some(i); } } return none; } /** * Removes one level of nesting * * ```ts * assert.deepStrictEqual(flatten([[1], [2], [3]]), [1, 2, 3]) * ``` */ export function flatten(mma) { return chain_(mma, identity); } /** * Copies a mutable array into an immutable */ export function fromMutable(as) { const l = as.length; if (l === 0) { return empty(); } const ras = Array(l); for (let i = 0; i < l; i++) { ras[i] = as[i]; } return ras; } /** * Get the first element in an array, or `None` if the array is empty * * ```ts * assert.deepStrictEqual(head([1, 2, 3]), some(1)) * assert.deepStrictEqual(head([]), none) * ``` */ export function head(as) { return isEmpty(as) ? none : some(as[0]); } /** * Test whether an array is empty * * ``` * assert.strictEqual(isEmpty([]), true) * ``` */ export function isEmpty(as) { return as.length === 0; } /** * Test whether an array is non empty narrowing down the type to `NonEmptyArray<A>` */ export function isNonEmpty(as) { return as.length > 0; } /** * Get the last element in an array, or `None` if the array is empty * * ```ts * assert.deepStrictEqual(last([1, 2, 3]), some(3)) * assert.deepStrictEqual(last([]), none) * ``` */ export function last(as) { return get_(as, as.length - 1); } /** * This function provides a safe way to read a value at a particular index from an array * * ```ts * assert.deepStrictEqual(get(1, [1, 2, 3]), some(2)) * assert.deepStrictEqual(get(3, [1, 2, 3]), none) * ``` */ export function get_(as, i) { return isOutOfBound(i, as) ? none : some(as[i]); } /** * This function provides a safe way to read a value at a particular index from an array * * @ets_data_first get_ */ export function get(i) { return as => get_(as, i); } /** * Return a list of length `n` with element `i` initialized with `f(i)` * * ```ts * const double = (n: number): number => n * 2 * assert.deepStrictEqual(makeBy_(5, double), [0, 2, 4, 6, 8]) * ``` */ export function makeBy_(n, f) { const r = []; for (let i = 0; i < n; i++) { r.push(f(i)); } return r; } /** * Return a list of length `n` with element `i` initialized with `f(i)` * * @ets_data_first makeBy_ */ export function makeBy(f) { return n => makeBy_(n, f); } /** * Apply f to every element of Array<A> returning Array<B> * * @ets_data_first map_ */ export function map(f) { return fa => fa.map(f); } /** * Apply f to every element of Array<A> returning Array<B> */ export function map_(fa, f) { return fa.map(f); } /** * Like map but also passes the index to f * * @ets_data_first mapWithIndex_ */ export function mapWithIndex(f) { return fa => mapWithIndex_(fa, f); } /** * Like map but also passes the index to f */ export function mapWithIndex_(fa, f) { return fa.map((a, i) => f(i, a)); } /** * Construct an array with a single element */ export function single(a) { return [a]; } /** * Create an array containing a range of integers, including both endpoints * * ```ts * assert.deepStrictEqual(range(1, 5), [1, 2, 3, 4, 5]) * ``` */ export function range(start, end) { return makeBy_(end - start + 1, i => start + i); } /** * Construct B by compacting with f over the array from left to right * * @ets_data_first reduce_ */ export function reduce(b, f) { return fa => reduce_(fa, b, f); } /** * Construct B by compacting with f over the array from left to right */ export function reduce_(fa, b, f) { return reduceWithIndex_(fa, b, (_, b, a) => f(b, a)); } /** * Construct B by compacting with f over the array from right to left * * @ets_data_first reduceRight_ */ export function reduceRight(b, f) { return fa => reduceRight_(fa, b, f); } /** * Construct B by compacting with f over the array from right to left * */ export function reduceRight_(fa, b, f) { return reduceRightWithIndex_(fa, b, (_, a, b) => f(a, b)); } /** * Construct B by compacting with f over the array from right to left * * @ets_data_first reduceRightWithIndex_ */ export function reduceRightWithIndex(b, f) { return fa => fa.reduceRight((b, a, i) => f(i, a, b), b); } /** * Construct B by compacting with f over the array from right to left * */ export function reduceRightWithIndex_(fa, b, f) { return fa.reduceRight((b, a, i) => f(i, a, b), b); } /** * Construct B by compacting with f over the array from left to right * * @ets_data_first reduceWithIndex_ */ export function reduceWithIndex(b, f) { return fa => reduceWithIndex_(fa, b, f); } /** * Construct B by compacting with f over the array from left to right */ export function reduceWithIndex_(fa, b, f) { const l = fa.length; let r = b; for (let i = 0; i < l; i++) { r = f(i, r, fa[i]); } return r; } /** * Create an array containing a value repeated the specified number of times * * ```ts * assert.deepStrictEqual(replicate_(3, 'a'), ['a', 'a', 'a']) * ``` */ export function replicate_(n, a) { return makeBy_(n, () => a); } /** * Create an array containing a value repeated the specified number of times * * ```ts * assert.deepStrictEqual(replicate_(3, 'a'), ['a', 'a', 'a']) * ``` * * @ets_data_first replicate_ */ export function replicate(a) { return n => replicate_(n, a); } /** * Reverse an array, creating a new array * * ```ts * assert.deepStrictEqual(reverse([1, 2, 3]), [3, 2, 1]) * ``` */ export function reverse(as) { return [...as].reverse(); } /** * Append an element to the end of an array, creating a new non empty array * * ```ts * assert.deepStrictEqual(append_([1, 2, 3], 4), [1, 2, 3, 4]) * ``` */ export function append_(init, end) { const len = init.length; const r = Array(len + 1); for (let i = 0; i < len; i++) { r[i] = init[i]; } r[len] = end; return r; } /** * Append an element to the end of an array, creating a new non empty array * * @ets_data_first append_ */ export function append(end) { return init => append_(init, end); } /** * Splits an array into two pieces, the first piece has `n` elements. * * ```ts * assert.deepStrictEqual(splitAt(2)([1, 2, 3, 4, 5]), [[1, 2], [3, 4, 5]]) * ``` * * @ets_data_first aplitAt_ */ export function splitAt(n) { return as => Tp.tuple(as.slice(0, n), as.slice(n)); } /** * Splits an array into two pieces, the first piece has `n` elements. */ export function splitAt_(as, n) { return Tp.tuple(as.slice(0, n), as.slice(n)); } /** * Get all but the first element of an array, creating a new array, or `None` if the array is empty * * ```ts * assert.deepStrictEqual(tail([1, 2, 3]), some([2, 3])) * assert.deepStrictEqual(tail([]), none) * ``` */ export function tail(as) { return isEmpty(as) ? none : some(as.slice(1)); } /** * Keep only a number of elements from the start of an array, creating a new array. * `n` must be a natural number * * ```ts * assert.deepStrictEqual(take(2)([1, 2, 3]), [1, 2]) * ``` * * @ets_data_first take_ */ export function take(n) { return as => as.slice(0, n); } /** * Keep only a number of elements from the start of an array, creating a new array. * `n` must be a natural number */ export function take_(as, n) { return as.slice(0, n); } export function takeWhile(predicate) { return as => takeWhile_(as, predicate); } export function takeWhile_(as, predicate) { const i = spanIndex_(as, predicate); const init = Array(i); for (let j = 0; j < i; j++) { init[j] = as[j]; } return init; } /** * Keep only a number of elements from the end of an array, creating a new array. * `n` must be a natural number * * ```ts * assert.deepStrictEqual(takeRight(2)([1, 2, 3, 4, 5]), [4, 5]) * ``` * * @ets_data_first takeRight_ */ export function takeRight(n) { return as => takeRight_(as, n); } /** * Keep only a number of elements from the end of an array, creating a new array. * `n` must be a natural number */ export function takeRight_(as, n) { return n === 0 ? empty() : as.slice(-n); } /** * Copies this array into a mutable one */ export function toMutable(ras) { const l = ras.length; const as = Array(l); for (let i = 0; i < l; i++) { as[i] = ras[i]; } return as; } /** * Construct A by unfolding B signaling end with an option */ export function unfold_(b, f) { const ret = []; let bb = b; // eslint-disable-next-line no-constant-condition while (true) { const mt = f(bb); if (isSome(mt)) { const [a, b] = mt.value.tuple; ret.push(a); bb = b; } else { break; } } return ret; } /** * Construct A by unfolding B signaling end with an option * * @ets_data_first unfold_ */ export function unfold(f) { return b => unfold_(b, f); } /** * The function is reverse of `zip`. Takes an array of pairs and return two corresponding arrays * * ```ts * assert.deepStrictEqual(unzip([[1, 'a'], [2, 'b'], [3, 'c']]), [[1, 2, 3], ['a', 'b', 'c']]) * ``` */ export function unzip(as) { const fa = []; const fb = []; for (let i = 0; i < as.length; i++) { fa[i] = as[i].get(0); fb[i] = as[i].get(1); } return Tp.tuple(fa, fb); } /** * Takes two arrays and returns an array of corresponding pairs. If one input array is short, excess elements of the * longer array are discarded * * ```ts * assert.deepStrictEqual(zip([1, 2, 3], ['a', 'b', 'c', 'd']), [[1, 'a'], [2, 'b'], [3, 'c']]) * ``` * @ets_data_first zip_ */ export function zip(fb) { return zipWith(fb, Tp.tuple); } /** * Takes two arrays and returns an array of corresponding pairs. If one input array is short, excess elements of the * longer array are discarded */ export function zip_(fa, fb) { return zipWith_(fa, fb, Tp.tuple); } /** * Apply a function to pairs of elements at the same index in two arrays, collecting the results in a new array. If one * input array is short, excess elements of the longer array are discarded. * * ```ts * assert.deepStrictEqual(zipWith([1, 2, 3], ['a', 'b', 'c', 'd'], (n, s) => s + n), ['a1', 'b2', 'c3']) * ``` */ export function zipWith_(fa, fb, f) { const fc = []; const len = Math.min(fa.length, fb.length); for (let i = 0; i < len; i++) { fc[i] = f(fa[i], fb[i]); } return fc; } /** * Apply a function to pairs of elements at the same index in two arrays, collecting the results in a new array. If one * input array is short, excess elements of the longer array are discarded. * * @ets_data_first zipWith_ */ export function zipWith(fb, f) { return fa => zipWith_(fa, fb, f); } /** * Constructs a new readonly array from an interable. */ export function from(as) { return Array.from(as); } /** * Joins together string arrays */ export function join_(as, s) { return as.join(s); } /** * Joins together string arrays * * @ets_data_first join_ */ export function join(s) { return as => as.join(s); } /** * A useful recursion pattern for processing an array to produce a new array, often used for "chopping" up the input * array. Typically chop is called with some function that will consume an initial prefix of the array and produce a * value and the rest of the array. * * @ets_data_first chop_ */ export function chop(f) { return as => chop_(as, f); } /** * A useful recursion pattern for processing an array to produce a new array, often used for "chopping" up the input * array. Typically chop is called with some function that will consume an initial prefix of the array and produce a * value and the rest of the array. */ export function chop_(as, f) { const result = []; let cs = as; while (isNonEmpty(cs)) { const { tuple: [b, c] } = f(cs); result.push(b); cs = c; } return result; } /** * Test whether an array contains a particular index */ export function isOutOfBound(i, as) { return i < 0 || i >= as.length; } /** * Finds the first index that doesn't satisfy predicate or the length of as */ export function spanIndex_(as, predicate) { const l = as.length; let i = 0; for (; i < l; i++) { if (!predicate(as[i])) { break; } } return i; } export function spanLeft(predicate) { return as => spanLeft_(as, predicate); } export function spanLeft_(as, predicate) { const i = spanIndex_(as, predicate); const init = Array(i); for (let j = 0; j < i; j++) { init[j] = as[j]; } const l = as.length; const rest = Array(l - i); for (let j = i; j < l; j++) { rest[j - i] = as[j]; } return { init, rest }; } /** * Returns the size of an array */ export function size(as) { return as.length; } /** * Returns true if all the elements of the array match a predicate */ export function forAll_(as, pred) { for (const a of as) { if (!pred(a)) { return false; } } return true; } /** * Returns true if all the elements of the array match a predicate * * @ets_data_first forAll_ */ export function forAll(pred) { return as => forAll_(as, pred); } /** * Returns true if any the elements of the array match a predicate */ export function forAny_(as, pred) { for (const a of as) { if (pred(a)) { return true; } } return false; } /** * Returns true if any the elements of the array match a predicate * * @ets_data_first forAny_ */ export function forAny(pred) { return as => forAny_(as, pred); } /** * Returns true if the array contains the element */ export function includes_(as, elem) { for (const a of as) { if (a === elem) { return true; } } return false; } /** * Returns true if the array contains the element * * @ets_data_first includes_ */ export function includes(elem) { return as => includes_(as, elem); } /** * Returns a copy of the array */ export function copy(as) { return as.slice(0); } //# sourceMappingURL=core.mjs.map