@prostojs/deserialize-fn

Overview

@prostojs/deserialize-fn is a utility library for JavaScript and TypeScript that provides functions to deserialize and execute JavaScript code strings in a given context. It includes a pool to cache functions for efficiency and a function to create new functions from code strings.

Installation

You can install @prostojs/deserialize-fn using npm:

npm install @prostojs/deserialize-fn

Or using pnpm:

pnpm install @prostojs/deserialize-fn

Usage

FNPool

A class that caches functions so that equal code-strings share the same function. This can improve performance by avoiding redundant function creation.

Methods

• call(code: string, ctx: C): R

  • Calls the function corresponding to the code string with the given context.

• getFn(code: string): (__ctx__: C) => R

  • Retrieves the function corresponding to the code string, creating and caching it if necessary.

Example

import { FNPool } from '@prostojs/deserialize-fn'

const pool = new FNPool<any, { value: number }>()

const code = 'return value * 2'
const context = { value: 5 }

const result = pool.call(code, context)
console.log(result) // Output: 10

deserializeFn

Generates a new function from a code string and returns it. The function is executed within the provided context, which can include global variables.

Parameters

• code (string): The code string to convert into a function.

Returns

• (__ctx__: CTX) => R: A new function that takes a context and returns the result of executing the code string.

Example

import { deserializeFn } from '@prostojs/deserialize-fn'

const code = 'return value * 2'
const context = { value: 5 }

const fn = deserializeFn<number, { value: number }>(code)
const result = fn(context)
console.log(result) // Output: 10

Globals

The deserializeFn function uses a GLOBALS object to provide a set of predefined global variables to the deserialized function. For security considerations, all potentially dangerous or sensitive globals are hidden from the function runtime. This prevents the deserialized code from accessing or modifying important global objects.

License

This project is licensed under the MIT License. See the LICENSE file for details.