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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

Cristian La Spina
Cristian La Spina
11,829 Points
Posted by Cristian La Spina
Cristian La Spina
11,829 Points

I don't understand what is wrong with my code

If I run index.js from the command prompt with the command "node index.js", it works just fine but the challenge task continues to refuse and tells me that it's wrong... mysteries of the task challenge...

index.js 
var utilities = require("./utilities");

var mailValues = {};

mailValues.first_name = "Janet";

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

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

//mergedContent === "Hi Janet! Thanks for completing this code challenge :)";
utilities.js 
function merge(content, values) {
    content = content.replace("%first_name%", values["first_name"]);
  return content;
}


module.exports.merge = merge;

2 Answers

Chris Shaw
Chris Shaw
26,676 Points
Chris Shaw
Chris Shaw
26,676 Points

Hi Cristian La Spina,

You have the right idea about how to replace the placeholders but the challenge is asking for you to take the gives values and find them in the string without hardcoding anything.

What does this mean?

We know that values is an objects and its keys are the name of the placeholders in the template therefore we can iterate over them to automatically search and replace the placeholders.

The simplest way of iterating values is to use a for...in loop which gives us access to all the placeholder keys needed for the replacement.

OK! What next?

MDN has a great resource on for...in loops which I highly recommend you read if you're not too familiar with them. https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/for...in

for (var placeholder in values) {
  // Replacement code goes here
  // content = content.replace(<placeholder>, <placeholder value>);
}

Giving out the answer would be far too simple, instead I have given you the starting point and it's up to you to fill in the blanks. i.e <placeholder> and <placeholder value>.

Happy coding!

Cristian La Spina
Cristian La Spina
11,829 Points
Cristian La Spina
Cristian La Spina
11,829 Points

Ah, ok, I got it! I didn't notice that the string to replace was the same as the property name, just surrounded by "%". Thanks