tryRequire

Wrap require in a try/catch block.

Installation

npm install @stdlib/utils-try-require

Alternatively,

To load the package in a website via a script tag without installation and bundlers, use the ES Module available on the esm branch (see README).
If you are using Deno, visit the deno branch (see README for usage intructions).
For use in Observable, or in browser/node environments, use the Universal Module Definition (UMD) build available on the umd branch (see README).

The branches.md file summarizes the available branches and displays a diagram illustrating their relationships.

To view installation and usage instructions specific to each branch build, be sure to explicitly navigate to the respective README files on each branch, as linked to above.

Usage

var tryRequire = require( '@stdlib/utils-try-require' );

tryRequire( id )

Wraps require in a try/catch block. If able to resolve a module id, the function returns the value bound to module.exports in the resolved module. Otherwise, the function returns an Error.

var x = tryRequire( 'beep' );

if ( x instanceof Error ) {
    console.log( x.message );
}

Notes

Use caution when attempting to resolve a relative path or a local module. This function attempts to resolve a module from its current path. Thus, the function is unable to resolve anything which is not along its search path. For local requires, use an absolute file path.
```
var resolve = require( 'path' ).resolve;

var out = tryRequire( resolve( '/foo/bar/baz', '..', 'lib', 'beep.js' ) );

if ( out instanceof Error ) {
    console.error( out.message );
}
```

Examples

var tryRequire = require( '@stdlib/utils-try-require' );

var out = tryRequire( '_abcdefghijklmnopqrstuvwxyz123456789_' );
if ( out instanceof Error ) {
    console.error( out.message );
} else {
    throw new Error( 'expected an error' );
}

out = tryRequire( '@stdlib/utils-try-require' );
if ( out !== tryRequire ) {
    throw new Error( 'expected export' );
}

Notice

This package is part of stdlib, a standard library for JavaScript and Node.js, with an emphasis on numerical and scientific computing. The library provides a collection of robust, high performance libraries for mathematics, statistics, streams, utilities, and more.

For more information on the project, filing bug reports and feature requests, and guidance on how to develop stdlib, see the main project repository.