Madonna Function

Creates a function that validates its arguments via madonna-fp, passing them to another function. You can optionally configure mapper functions to modify the arguments after validation. I created this because I often want to call a function and know for certain the arguments are valid. The optional mapper is for convenience since I also often need arguments to come in as raw json and passed through a class or constructor. The mapping functionality is provided by madonna-map.

Tested against

• node 0.10.0 for the (default) es5 version
• node 6.0.0 for es6 @ require('madonna-function/es6')

Table of Contents

• Examples
• API

Examples

const createMadonnaFn = require('madonna-function').create
  , printArgs = console.dir.bind(console);

// creates a function requiring the argument 'name' and prints it
let mfn = createMadonnaFn({
  marg: { name: ['require', 'isLadenString'] }
  , fn: printArgs
});

mfn({ name: 'matt' });
// prints
// { name: 'matt' }


// lets do the same but map name to all uppercase letters
let mfn = createMadonnaFn({
  marg: { name: ['require', 'isLadenString'] }
  , fn: printArgs
  , argMap: { name: fp.toUpper }
});

mfn({ name: 'matt' });
// prints
// { name: 'MATT' }


// madonna-fp validation errors will be thrown if you pass invalid arguments
mfn({ name: 1 });
// throws the error
// Invalid Input: The following arguments didn't pass their criterion
// invalid arguments and values: {
//   "name": 1
// }
// failed criterion per argument: {
//   "name": {
//     "flags": [
//       "isLadenString"
//     ]
//   }
// }

API

require('madonna-function').create

• Takes the following arguments
  • marg: require isLadenPlainObject
    • marg stands for 'madonna-fp argument'. It is passed to madonna-fp which is used to validate the arguments in calls to the returned function.
  • fn: require fp.isFunction
    • The function called with the validated, and possibly mapped arguments
  • argMap: isLadenPlainObject
    • An object with keys present in marg to functions whose input will be the validated value, and output will be passed to fn. Examples above should clarify any confusion.
• Returns a function that validates its input against marg. Any properties in argMap will pass through their mappers. All validated and mapped values will be passed into fn.