node-dynamic-function

Easily create functions with dynamic name and length. This is useful for wrapping functions without f'ing up their name and length.

Install

npm install --save dynamic-function

Usage

const dynamicFunction = require('dynamic-function');
 
function originalFunction(originalArg1, originalArg2) {
    /* ... */
}
 
const wrappedFunction = dynamicFunction(originalFunction, {
  name: 'wrapped_' + originalFunction.name,
  length: originalFunction.length,
});
 
console.log(wrappedFunction.name);   // logs 'wrapped_originalFunction'
console.log(wrappedFunction.length); // logs 2
 
console.log(wrappedFunction.toString());
 
// function wrapped_originalFunction(originalArg1, originalArg2) {
//   /* ... */
// }

API

dynamicFunction ( func [, options] ) func : function options : object (optional) options.bind : object (default: null) options.name : string (default: '') options.length : number (default: 0)

Performance

Some environments (eg. NodeJS < 4.x.x) don't support renaming functions with Object.defineProperty. In this case there is a fallback to eval.

eval a relatively slow JavaScript feature. Avoid (over)using this in situations where high performance is required.

At start-up (for Server applications) / low load situations using this should pose no problem.