stdlib-js
<summary>
About stdlib...
</summary>
We believe in a future in which the web is a preferred environment for numerical computation. To help realize this future, we've built stdlib. stdlib is a standard library, with an emphasis on numerical and scientific computation, written in JavaScript (and C) for execution in browsers and in Node.js.
The library is fully decomposable, being architected in such a way that you can swap out and mix and match APIs and functionality to cater to your exact preferences and use cases.
When you use stdlib, you can be absolutely certain that you are using the most thorough, rigorous, well-written, studied, documented, tested, measured, and high-quality code out there.
To join us in bringing numerical computing to the web, get started by checking us out on GitHub, and please consider financially supporting stdlib. We greatly appreciate your continued support!
Write File
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Write data to a file.
bash
npm install @stdlib/fs-write-file
javascript
var writeFile = require( '@stdlib/fs-write-file' );
#### writeFile( file, data[, options], clbk )
Asynchronously write data to a file.
javascript
var join = require( 'path' ).join;
var fpath = join( __dirname, 'examples', 'fixtures', 'file.txt' );
writeFile( fpath, 'beep boop\n', onWrite );
function onWrite( error ) {
if ( error ) {
throw error;
}
}
The data argument may be either a string or a [Buffer][@stdlib/buffer/ctor].
javascript
var join = require( 'path' ).join;
var string2buffer = require( '@stdlib/buffer-from-string' );
var fpath = join( __dirname, 'examples', 'fixtures', 'file.txt' );
writeFile( fpath, string2buffer( 'beep boop\n' ), onWrite );
function onWrite( error ) {
if ( error ) {
throw error;
}
}
The function accepts the same options and has the same defaults as [fs.writeFile()][node-fs].
#### writeFile.sync( file, data[, options] )
Synchronously writes data to a file.
javascript
var join = require( 'path' ).join;
var fpath = join( __dirname, 'examples', 'fixtures', 'file.txt' );
var err = writeFile.sync( fpath, 'beep boop\n' );
if ( err instanceof Error ) {
throw err;
}
The function accepts the same options and has the same defaults as [fs.writeFileSync()][node-fs].
writeFile.sync and [fs.writeFileSync()][node-fs] is that [fs.writeFileSync()][node-fs] will throw if an error is encountered (e.g., if given a non-existent directory path) and this API will return an error. Hence, the following anti-pattern
javascript
var fs = require( 'fs' );
// Check for directory path existence to prevent an error being thrown...
if ( fs.existsSync( '/path/to' ) ) {
fs.writeFileSync( '/path/to/file.txt', 'beep boop\n' );
}
can be replaced by an approach which addresses existence via error handling.
javascript
var writeFile = require( '@stdlib/fs-write-file' );
// Explicitly handle the error...
var err = writeFile.sync( '/path/to/file.txt', 'beep boop\n' );
if ( err instanceof Error ) {
// You choose what to do...
throw err;
}
javascript
var join = require( 'path' ).join;
var writeFile = require( '@stdlib/fs-write-file' );
var fpath = join( __dirname, 'examples', 'fixtures', 'file.txt' );
// Synchronously write data to a file:
var err = writeFile.sync( fpath, 'beep boop\n', 'utf8' );
// returns null
console.log( err instanceof Error );
// => false
// Asynchronously write data to a file:
writeFile( fpath, 'beep boop\n', onWrite );
function onWrite( error ) {
if ( error ) {
console.error( 'Error: %s', error.message );
}
console.log( 'Success!' );
}
@stdlib/fs-write-file-cli][@stdlib/fs-write-file-cli]: CLI package for use as a command-line utility.
- [@stdlib/fs-exists][@stdlib/fs/exists]: test whether a path exists on the filesystem.
- [@stdlib/fs-read-file][@stdlib/fs/read-file]: read the entire contents of a file.
