@marxus/babel-plugin-transform-property-prefix-symbol v0.0.4

babel-plugin-transform-property-prefix-symbol

transforms prefixed named properties to computed Symbol.for properties

Example

In

// { prefixes: ["s_", "_x"] }
foo
  .s_filter(x => x)
  .s_thru(y => y)
  ._xmap(z => z);

Out

var _symbolFor = Symbol.for;

foo
  [_symbolFor("s_filter")](x => x)
  [_symbolFor("s_thru")](y => y)
  [_symbolFor("_xmap")](z => z);

Use case (at least, my own)

extending the Object prototype with properties that: 1. are not iterable (it's a symbol property, loops and such work on named properties) 2. won't get accidentally overwritten by another property assignment 3. won't accidentally overwrite existing properties 4. enables nice chaining without a wrapper

// { prefixes: ["ס_"] } // any viable unicode javascript variable name is okay.
Object.prototype.ס_reduce = function(...args) {
  return _.reduce(this, ...args);
};

const obj = { a: 1, b: 2, c: 3 };

obj.ס_reduce((result, value, key) => {
  result[key] = value * 2;
  return result;
}, { });

WTF is "ס" in your example?

"ס" is the hebrew character that sounds like S (Symbol) and also the first character for the hebrew words "Semel" and "Siman" (which both translates to Symbol) just my personal pick for a prefix, pick your own...

Installation

$ npm install @marxus/babel-plugin-transform-property-prefix-symbol --save-dev

Usage

Via .babelrc (Recommended)

.babelrc

{
  "plugins": [
    [
      "@marxus/transform-property-prefix-symbol",
      { "prefixes": ["s_"] }
    ]
  ]
}

Via Node API

require("babel-core").transform("code", {
  plugins: [
    [
      "@marxus/transform-property-prefix-symbol",
      { prefixes: ["s_"] }
    ]
  ]
});