iteragain
Version:
Javascript Iterable/Iterator/Generator-function utilities.
44 lines • 1.79 kB
JavaScript
"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.WindowsIterator = void 0;
/** An Iterator that yields windows or tuples of various sizes and offsets/intervals from the input `iterator`. */
class WindowsIterator {
constructor(iterator, length, offset, fill) {
this.iterator = iterator;
this.length = length;
this.offset = offset;
this.fill = fill;
this.prev = [];
this.nextResult = { done: false, value: undefined };
if (length <= 0)
throw new RangeError('length must be greater than 0');
if (offset <= 0)
throw new RangeError('offset must be greater than 0');
this.unused = this.offset - this.length;
}
[Symbol.iterator]() {
return this;
}
next(...args) {
if (this.nextResult.done)
return this.nextResult;
while (this.prev.length < this.length && !(this.nextResult = this.iterator.next(...args)).done)
this.prev.push(this.nextResult.value);
if (this.prev.length < this.length) {
if (this.fill === undefined || !this.prev.length)
return this.nextResult;
for (let i = this.prev.length; i < this.length; i++)
this.prev.push(this.fill);
// this.prev.push(...Array.from({ length: this.length - this.prev.length }, _ => this.fill));
}
// Remove unused elements:
for (let i = 0; i < this.unused; i++)
this.iterator.next(...args);
const value = this.prev.slice();
this.prev.splice(0, this.offset);
return { done: false, value };
}
}
exports.WindowsIterator = WindowsIterator;
exports.default = WindowsIterator;
//# sourceMappingURL=WindowsIterator.js.map