polyfill Object.entries for browser builds.

dist/lindenmayer.browser.js

@@ -1,6 +1,22 @@
 var LSystem = (function () {
   'use strict';
 
+  {
+    if (!Object.entries) {
+      Object.entries = function (obj) {
+        var ownProps = Object.keys(obj),
+            i = ownProps.length,
+            resArray = new Array(i); // preallocate the Array
+
+        while (i--) {
+          resArray[i] = [ownProps[i], obj[ownProps[i]]];
+        }
+
+        return resArray;
+      };
+    }
+  }
+
   // Get a list of productions that have identical initiators,
   // Output a single stochastic production. Probability per production
   // is defined by amount of input productions (4 => 25% each, 2 => 50% etc.)

docs/examples/lindenmayer.js

@@ -1,6 +1,22 @@
 var LSystem = (function () {
   'use strict';
 
+  {
+    if (!Object.entries) {
+      Object.entries = function (obj) {
+        var ownProps = Object.keys(obj),
+            i = ownProps.length,
+            resArray = new Array(i); // preallocate the Array
+
+        while (i--) {
+          resArray[i] = [ownProps[i], obj[ownProps[i]]];
+        }
+
+        return resArray;
+      };
+    }
+  }
+
   // Get a list of productions that have identical initiators,
   // Output a single stochastic production. Probability per production
   // is defined by amount of input productions (4 => 25% each, 2 => 50% etc.)

lindenmayer.js

@@ -1,3 +1,4 @@
+import './polyfills/objectEntries'
 import {
   transformClassicStochasticProductions,
   transformClassicCSProduction,

package.json

@@ -1,7 +1,7 @@
 {
   "name": "lindenmayer",
   "description": "Lindenmayer is  a L-System/LSystem library using modern (ES6) JavaScript with focus on a concise syntax. The idea is to have a very powerful but simple base functionality, that can handle most use-cases by simply allowing anonymous functions as productions, which makes it very flexible in comparison to classic L-Systems.",
-  "version": "1.5.1",
+  "version": "1.5.2",
   "author": "Tom Brewe <info@nylkiway.net>",
   "license": "MIT",
   "keywords": [
@@ -58,6 +58,7 @@
     "npm-run-all": "^4.1.5",
     "rollup": "^1.16.0",
     "rollup-plugin-babel": "^4.3.2",
+    "rollup-plugin-replace": "^2.2.0",
     "rollup-plugin-terser": "^5.0.0"
   },
   "dependencies": {}

polyfills/objectEntries.js

@@ -0,0 +1,13 @@
+if('__BUILD_FORMAT__' === 'browser') {
+  if (!Object.entries) {
+    Object.entries = function( obj ){
+      var ownProps = Object.keys( obj ),
+      i = ownProps.length,
+      resArray = new Array(i); // preallocate the Array
+      while (i--)
+      resArray[i] = [ownProps[i], obj[ownProps[i]]];
+
+      return resArray;
+    };
+  }
+}

rollup.browser.config.js

@@ -1,5 +1,8 @@
 import babel from 'rollup-plugin-babel';
+// import commonjs from 'rollup-plugin-commonjs';
+// import resolve from 'rollup-plugin-node-resolve';
 import { terser } from 'rollup-plugin-terser';
+import replace from 'rollup-plugin-replace';
 
 let minifyEnv = process.env.minify || false;
 
@@ -13,11 +16,15 @@ let output = [
 
 const babelConf = {
   babelrc: false,
+  // https://github.com/rollup/rollup-plugin-babel/issues/254#issuecomment-423799147
+  // exclude: [/\/core-js\//],
   presets: [
     ['@babel/preset-env', {
       targets: {
         ie: 11
       },
+      // useBuiltIns: 'entry',
+      // corejs: {version: 3},
       modules: false,
       loose: true
     }]
@@ -29,6 +36,21 @@ export default {
   input: 'lindenmayer.js',
   output,
   plugins: [
+  replace({
+    include: 'polyfills/**',
+    "__BUILD_FORMAT__": 'browser'
+    }),
+
+    // resolve({
+    //   // only: [ 'core-js' ]
+    // }),
+    // commonjs({
+    //   // non-CommonJS modules will be ignored, but you can also
+    //   // specifically include/exclude files
+    //   include: 'node_modules/**',  // Default: undefined
+    //   // if false then skip sourceMap generation for CommonJS modules
+    //   sourceMap: false,  // Default: true
+    // }),
     babel(babelConf),
     minifyEnv ? terser({
       ecma: '5',