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JavaScript Build a Simple Dynamic Site with Node.js Creating a Basic Template Engine in Node.js A Simple Merge Utility

Tried using the replace method but totally failed to work

its as if the replace object its not recognised
var utilities = require("./utilities");
var fs = require("fs");

var mailValues = {};

mailValues.first_name = "Janet";

var emailTemplate = fs.readFile("Hi %first_name%! Thanks for completing this code challenge :)");

var mergedContent = utilities.merge(emailTemplate, mailValues);

//mergedContent === "Hi Janet! Thanks for completing this code challenge :)";
function merge(content, values) {
  for(let key in values){
    content =  content.replace("{{"+ key +"}}",values[key]);
  return content

module.exports.merge = merge;

2 Answers

Steven Parker
Steven Parker
229,005 Points

Your content argument may be undefined or null.

I notice you're passing the return value from fs.readFile to your merge method, but I don't think it actually returns anything. I would also expect it to need different arguments.

Please take a look at the documentation page covering fs.readFile for proper usage information. I might also be that you intended to do something else there entirely.

Mark Warren
Mark Warren
19,251 Points

It's pretty similar to the function in renderer.js, except in this case the value you're replacing is wrapped with %..% instead of {{...}}

function merge(content, values) {
  for (let key in values) {
    content = content.replace("%" + key + "%", values[key]);
  return content;

module.exports.merge = merge;