refactoring

Resolve #7779

1 files changed, 0 insertions, 138 deletions

diff --git a/src/prelude/array.ts b/src/prelude/array.ts
deleted file mode 100644
index d63f0475d0..0000000000
--- a/src/prelude/array.ts
+++ /dev/null
@@ -1,138 +0,0 @@
-import { EndoRelation, Predicate } from './relation';
-
-/**
- * Count the number of elements that satisfy the predicate
- */
-
-export function countIf<T>(f: Predicate<T>, xs: T[]): number {
-	return xs.filter(f).length;
-}
-
-/**
- * Count the number of elements that is equal to the element
- */
-export function count<T>(a: T, xs: T[]): number {
-	return countIf(x => x === a, xs);
-}
-
-/**
- * Concatenate an array of arrays
- */
-export function concat<T>(xss: T[][]): T[] {
-	return ([] as T[]).concat(...xss);
-}
-
-/**
- * Intersperse the element between the elements of the array
- * @param sep The element to be interspersed
- */
-export function intersperse<T>(sep: T, xs: T[]): T[] {
-	return concat(xs.map(x => [sep, x])).slice(1);
-}
-
-/**
- * Returns the array of elements that is not equal to the element
- */
-export function erase<T>(a: T, xs: T[]): T[] {
-	return xs.filter(x => x !== a);
-}
-
-/**
- * Finds the array of all elements in the first array not contained in the second array.
- * The order of result values are determined by the first array.
- */
-export function difference<T>(xs: T[], ys: T[]): T[] {
-	return xs.filter(x => !ys.includes(x));
-}
-
-/**
- * Remove all but the first element from every group of equivalent elements
- */
-export function unique<T>(xs: T[]): T[] {
-	return [...new Set(xs)];
-}
-
-export function sum(xs: number[]): number {
-	return xs.reduce((a, b) => a + b, 0);
-}
-
-export function maximum(xs: number[]): number {
-	return Math.max(...xs);
-}
-
-/**
- * Splits an array based on the equivalence relation.
- * The concatenation of the result is equal to the argument.
- */
-export function groupBy<T>(f: EndoRelation<T>, xs: T[]): T[][] {
-	const groups = [] as T[][];
-	for (const x of xs) {
-		if (groups.length !== 0 && f(groups[groups.length - 1][0], x)) {
-			groups[groups.length - 1].push(x);
-		} else {
-			groups.push([x]);
-		}
-	}
-	return groups;
-}
-
-/**
- * Splits an array based on the equivalence relation induced by the function.
- * The concatenation of the result is equal to the argument.
- */
-export function groupOn<T, S>(f: (x: T) => S, xs: T[]): T[][] {
-	return groupBy((a, b) => f(a) === f(b), xs);
-}
-
-export function groupByX<T>(collections: T[], keySelector: (x: T) => string) {
-	return collections.reduce((obj: Record<string, T[]>, item: T) => {
-		const key = keySelector(item);
-		if (!obj.hasOwnProperty(key)) {
-			obj[key] = [];
-		}
-
-		obj[key].push(item);
-
-		return obj;
-	}, {});
-}
-
-/**
- * Compare two arrays by lexicographical order
- */
-export function lessThan(xs: number[], ys: number[]): boolean {
-	for (let i = 0; i < Math.min(xs.length, ys.length); i++) {
-		if (xs[i] < ys[i]) return true;
-		if (xs[i] > ys[i]) return false;
-	}
-	return xs.length < ys.length;
-}
-
-/**
- * Returns the longest prefix of elements that satisfy the predicate
- */
-export function takeWhile<T>(f: Predicate<T>, xs: T[]): T[] {
-	const ys = [];
-	for (const x of xs) {
-		if (f(x)) {
-			ys.push(x);
-		} else {
-			break;
-		}
-	}
-	return ys;
-}
-
-export function cumulativeSum(xs: number[]): number[] {
-	const ys = Array.from(xs); // deep copy
-	for (let i = 1; i < ys.length; i++) ys[i] += ys[i - 1];
-	return ys;
-}
-
-export function toArray<T>(x: T | T[] | undefined): T[] {
-	return Array.isArray(x) ? x : x != null ? [x] : [];
-}
-
-export function toSingle<T>(x: T | T[] | undefined): T | undefined {
-	return Array.isArray(x) ? x[0] : x;
-}