time-to-botec

Benchmark sampling in different programming languages
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object_mode.js (2696B)

      1 /**
      2 * @license Apache-2.0
      3 *
      4 * Copyright (c) 2018 The Stdlib Authors.
      5 *
      6 * Licensed under the Apache License, Version 2.0 (the "License");
      7 * you may not use this file except in compliance with the License.
      8 * You may obtain a copy of the License at
      9 *
     10 *    http://www.apache.org/licenses/LICENSE-2.0
     11 *
     12 * Unless required by applicable law or agreed to in writing, software
     13 * distributed under the License is distributed on an "AS IS" BASIS,
     14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     15 * See the License for the specific language governing permissions and
     16 * limitations under the License.
     17 */
     18 
     19 'use strict';
     20 
     21 // MODULES //
     22 
     23 var isObject = require( '@stdlib/assert/is-plain-object' );
     24 var copy = require( '@stdlib/utils/copy' );
     25 var Stream = require( './main.js' );
     26 
     27 
     28 // MAIN //
     29 
     30 /**
     31 * Returns a transform stream with `objectMode` set to `true`.
     32 *
     33 * @param {Options} [options] - stream options
     34 * @param {Function} [options.transform] - callback to invoke upon receiving a new chunk
     35 * @param {Function} [options.flush] - callback to invoke after receiving all chunks and prior to the stream closing
     36 * @param {(string|null)} [options.encoding=null] - specifies how `Buffer` objects should be decoded to `strings`
     37 * @param {NonNegativeNumber} [options.highWaterMark] - specifies the `Buffer` level for when `write()` starts returning `false`
     38 * @param {boolean} [options.allowHalfOpen=false] - specifies whether the stream should remain open even if one side ends
     39 * @param {boolean} [options.decodeStrings=true] - specifies whether to decode `strings` into `Buffer` objects when writing
     40 * @throws {TypeError} options argument must be an object
     41 * @throws {TypeError} must provide valid options
     42 * @returns {TransformStream} transform stream
     43 *
     44 * @example
     45 * var stdout = require( '@stdlib/streams/node/stdout' );
     46 *
     47 * function stringify( chunk, enc, clbk ) {
     48 *     clbk( null, JSON.stringify( chunk ) );
     49 * }
     50 *
     51 * function newline( chunk, enc, clbk ) {
     52 *     clbk( null, chunk+'\n' );
     53 * }
     54 *
     55 * var s1 = objectMode({
     56 *     'transform': stringify
     57 * });
     58 *
     59 * var s2 = objectMode({
     60 *     'transform': newline
     61 * });
     62 *
     63 * s1.pipe( s2 ).pipe( stdout );
     64 *
     65 * s1.write( {'value': 'a'} );
     66 * s1.write( {'value': 'b'} );
     67 * s1.write( {'value': 'c'} );
     68 *
     69 * s1.end();
     70 *
     71 * // prints: '{"value":"a"}\n{"value":"b"}\n{"value":"c"}\n'
     72 */
     73 function objectMode( options ) {
     74 	var opts;
     75 	if ( arguments.length ) {
     76 		if ( !isObject( options ) ) {
     77 			throw new TypeError( 'invalid argument. Options argument must be an object. Value: `' + options + '`.' );
     78 		}
     79 		opts = copy( options );
     80 	} else {
     81 		opts = {};
     82 	}
     83 	opts.objectMode = true;
     84 	return new Stream( opts );
     85 }
     86 
     87 
     88 // EXPORTS //
     89 
     90 module.exports = objectMode;