[go: up one dir, main page]

Skip to content

Convert JS functions to runnable strings. With parameter serialization!

License

Notifications You must be signed in to change notification settings

meyfa/runstring

Repository files navigation

runstring

CI Test Coverage Maintainability

Convert JS functions to runnable strings, with parameter serialization! (We also support TypeScript natively!)

This was made for Electron's executeJavaScript() method, so that the code does not need to be constructed as a string but can be passed as a function. runstring will convert that function and its parameters to an IIFE string.

The following parameter types are supported:

  • Literals null, undefined, true, false
  • Numbers
  • Strings
  • Functions (both standard notation and arrow notation)
  • Arrays
  • Objects

Strings will be escaped. Nesting of values (in objects and arrays) is supported without limit.

Usage

Basic Usage

Simply invoke the module with a function and its parameters to obtain the IIFE string.

const runstring = require('runstring')

const code = runstring(myFunction, arg1, arg2 /* , ... */)
// do something with `code`

Example 1

const runstring = require('runstring')

const code = runstring(function (a, b) {
  return a + b
}, 5, 7)

code would now store a string similar to this: ';(function (a, b) { return a + b })(5, 7);'. That string could be passed to Electron's executeJavaScript(), or the standard eval() (eval is evil, but if you have your reasons to use it, might as well do it right).

Example 2

Any parameter type is supported — numbers, strings, objects, arrays, and even other functions can all be passed to the module for stringification:

const runstring = require('runstring')

const code = runstring(function (predicate, action) {
  const elements = document.getElementsByClassName('item')
  for (let i = 0; i < elements.length; ++i) {
    if (predicate(elements[i])) {
      action(elements[i])
    }
  }
}, (e) => e.tagName.toLowerCase() === 'div', removeElement)

function removeElement (e) {
  e.parentNode.removeChild(e)
}

code would now store the following string:

';(function (predicate, action) {
  const elements = document.getElementsByClassName('item')
  for (let i = 0; i < elements.length; ++i) {
    if (predicate(elements[i])) {
      action(elements[i])
    }
  }
})((e) => e.tagName.toLowerCase() === 'div', function removeElement (e) {
  e.parentNode.removeChild(e)
});'