--- title: Value is stream type: snippet tags: [node,type] cover: mountain-lake-cottage-2 dateModified: 2020-10-20T23:02:01+03:00 --- Checks if the given argument is a stream. - Check if the value is different from `null`. - Use `typeof` to check if the value is of type `object` and the `pipe` property is of type `function`. ```js const isStream = val => val !== null && typeof val === 'object' && typeof val.pipe === 'function'; ``` ```js const fs = require('fs'); isStream(fs.createReadStream('test.txt')); // true ```