Explained with more details methods and techniques that are used, usage example with inline input and output data, modified snippet code to be compliant with guidelines

snippets/reducedFilter.md

@@ -15,24 +15,64 @@ properties of original objects
 
 #### Info
 
-Used ES6 reduce 
-Dummy data for testing 
-Generated with http://www.mockaroo.com/ 
+Used ES6 Array.reduce() in order to filter an array with objects based on condition.
+If condition is met, then Array.reduce is used again to construct object with the predefined properties. Further more, in order to evaluate condition based in object properties item, must be passed through window to Function constructor. Finally, when new object is constructed then it is saved in the output array. 
 
 ```js
+const safeEval = (condition) => new Function('return '+condition)();
+
 const reducedFilter = (data, condition, outputProps) => 
     data.reduce( (acc, item) => {
-    if(eval(condition)) {
+    window.item = item;
+    if(safeEval(condition)) {
       const parsedObj = outputProps.reduce( (aggr, index) => {
         aggr[index] = item[`${index}`];
         return aggr;
       }, {});
-      acc.push(parsedObj); 
+      acc[acc.length]=parsedObj; 
     } 
     return (acc);
   }, []);
+  /*
+  Usage example:
+
+  Input data sample is an array of Objects
+
+  const data = [{
+  "id": 1,
+  "first_name": "Jo",
+  "last_name": "Blackstone",
+  "email": "jblackstone0@yahoo.co.jp",
+  "gender": "Male",
+  "ip_address": "255.171.18.115"
+}, ... ]
+
+const condition = `window.item.first_name[0] ==='B'`;
+
+const outputProps = ['first_name','id', 'last_name', 'ip_address'];
+
+const output = reducedFilter(data, condition, outputProps); -->
+
+Output conditionally filtered data sample. Properties of output objects are subset of 
+the properties of the original objects. 
+
+Filtered output data :
+
+[
+Object {
+  first_name: "Bertina",
+  id: 6,
+  ip_address: "33.239.93.222",
+  last_name: "Pinching"
+},
+Object {
+  first_name: "Beckie",
+  id: 13,
+  ip_address: "239.111.225.202",
+  last_name: "Thomesson"
+}, ... ]
+
+
+  */
 ```
-#### Usage Example available in :
-
-`https://codepen.io/myapos/pen/dJGByW?editors=0112`