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!
Read File
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Read the entire contents of a file.
bash
npm install @stdlib/fs-read-file
javascript
var readFile = require( '@stdlib/fs-read-file' );
#### readFile( file[, options], clbk )
Asynchronously reads the entire contents of a file.
javascript
readFile( __filename, onFile );
function onFile( error, data ) {
if ( error ) {
throw error;
}
console.log( data );
}
The function accepts the same options and has the same defaults as [fs.readFile()][node-fs].
#### readFile.sync( file[, options] )
Synchronously reads the entire contents of a file.
javascript
var out = readFile.sync( __filename );
if ( out instanceof Error ) {
throw out;
}
console.log( out );
The function accepts the same options and has the same defaults as [fs.readFileSync()][node-fs].
fs.readFileSync()][node-fs] is that [fs.readFileSync()][node-fs] will throw if an error is encountered (e.g., if given a non-existent path) and this API will return an error. Hence, the following anti-pattern
javascript
var fs = require( 'fs' );
var file = '/path/to/file.js';
// Check for existence to prevent an error being thrown...
if ( fs.existsSync( file ) ) {
file = fs.readFileSync( file );
}
can be replaced by an approach which addresses existence via error handling.
javascript
var readFile = require( '@stdlib/fs-read-file' );
var file = '/path/to/file.js';
// Explicitly handle the error...
file = readFile.sync( file );
if ( file instanceof Error ) {
// You choose what to do...
console.error( file.message );
}
javascript
var readFile = require( '@stdlib/fs-read-file' );
/* Sync */
var file = readFile.sync( __filename, 'utf8' );
// returns <string>
console.log( file instanceof Error );
// => false
file = readFile.sync( 'beepboop', {
'encoding': 'utf8'
});
// returns <Error>
console.log( file instanceof Error );
// => true
/* Async */
readFile( __filename, onFile );
readFile( 'beepboop', onFile );
function onFile( error, data ) {
if ( error ) {
if ( error.code === 'ENOENT' ) {
console.error( 'File does not exist.' );
} else {
throw error;
}
} else {
console.log( data );
}
}
@stdlib/fs-read-file-cli][@stdlib/fs-read-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-open][@stdlib/fs/open]: open a file.
- [@stdlib/fs-read-dir][@stdlib/fs/read-dir]: read the entire contents of a directory.
- [@stdlib/fs-read-json][@stdlib/fs/read-json]: read a file as JSON.
- [@stdlib/fs-write-file][@stdlib/fs/write-file]: write data to a file.
