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@stdlib/streams

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/** * @license Apache-2.0 * * Copyright (c) 2018 The Stdlib Authors. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ 'use strict'; // MODULES // var isObject = require( '@stdlib/assert/is-plain-object' ); var format = require( '@stdlib/string/format' ); var assign = require( '@stdlib/object/assign' ); var ArrayStream = require( './main.js' ); // MAIN // /** * Returns a function for creating readable streams from array-like objects. * * @param {Options} [options] - stream options * @param {boolean} [options.objectMode=false] - specifies whether a stream should operate in object mode * @param {(string|null)} [options.encoding=null] - specifies how `Buffer` objects should be decoded to `strings` * @param {NonNegativeNumber} [options.highWaterMark] - specifies the maximum number of bytes to store in an internal buffer before pausing streaming * @param {string} [options.sep='\n'] - separator used to join streamed data * @param {Function} [options.serialize] - custom serialization function * @param {integer} [options.dir=1] - iteration direction * @throws {TypeError} options argument must be an object * @returns {Function} stream factory * * @example * var Float64Array = require( '@stdlib/array/float64' ); * var randu = require( '@stdlib/random/base/randu' ); * * var arr = new Float64Array( 10 ); * var i; * for ( i = 0; i < arr.length; i++ ) { * arr[ i ] = randu(); * } * * var opts = { * 'sep': ',', * 'objectMode': false, * 'encoding': 'utf8', * 'highWaterMark': 64 * }; * * var createStream = factory( opts ); * * // Create 10 identically configured streams... * var streams = []; * for ( i = 0; i < 10; i++ ) { * streams.push( createStream( arr ) ); * } */ function factory( options ) { var opts; if ( arguments.length ) { if ( !isObject( options ) ) { throw new TypeError( format( 'invalid argument. Options argument must be an object. Value: `%s`.', options ) ); } opts = assign( {}, options ); } else { opts = {}; } return createStream; /** * Returns a readable stream from an array-like object. * * @private * @param {Collection} src - source array-like object * @throws {TypeError} must provide an array-like object * @throws {TypeError} options argument must be an object * @throws {TypeError} must provide valid options * @returns {ArrayStream} Stream instance */ function createStream( src ) { return new ArrayStream( src, opts ); } } // EXPORTS // module.exports = factory;