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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

Aaron HARPT
Aaron HARPT
19,845 Points
Posted by Aaron HARPT
Aaron HARPT
19,845 Points

Code challenge question

I am having trouble with the following code challenge:

Complete the implementation of the merge method in utilities.js file. You should be able to pass in a string with placeholders with percent signs (%) surrounding them. The second parameter should be an object with values to be inserted in to the placeholders. Look at index.js to see how it should work.

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) {

  return content;
}


module.exports.merge = merge;

5 Answers

Yawar Jamal
Yawar Jamal
606 Points

Hey Aaron, nice that youworked upon it . So you are very close except that in your replace function instead of using "{" "}" you are suppose to use "%" + key + "%"

Michael Walker
Michael Walker
45,428 Points
Michael Walker
Michael Walker
45,428 Points

Hi Aaron,

Your answer is very similar to mine in that we both followed Andrew's example in the lesson by cycling over the keys using a loop. The only difference here is the test gives you further instructions of using percent signs instead of brackets. You do seem to have the answer already, just in the wrong format so I'll paste my answer here:

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

module.exports.merge = merge;

Hope it helps!

Michael Walker
Michael Walker
45,428 Points
Michael Walker
Michael Walker
45,428 Points 
function merge(content, values) {
  for (var key in values) {
    content = content.replace("%" + key + "%", values[key]);
  return content;
}

module.exports.merge = merge;
Juliette Tworsey
seal-mask
.a{fill-rule:evenodd;}techdegree seal-36
Juliette Tworsey
Front End Web Development Techdegree Graduate 32,425 Points
Juliette Tworsey
.a{fill-rule:evenodd;}techdegree seal-36
Juliette Tworsey
Front End Web Development Techdegree Graduate 32,425 Points

It took some trial and error, but this is what inevitably worked for me:

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

}

module.exports.merge = merge;

Caleb Kleveter
MOD
Caleb Kleveter
Treehouse Moderator 37,862 Points
Caleb Kleveter
Caleb Kleveter
Treehouse Moderator 37,862 Points

Hi Aaron :^)

Not sure what your ideas are to solve this, but could you use an if loop? Not much of a hint, just trying to help.

Yawar Jamal
Yawar Jamal
606 Points
Yawar Jamal
Yawar Jamal
606 Points

Hi Aaron,

So the problem is complete the merge function so that it replaces the placeholders with the correct value (although merge "name for function" doesn't sound right with the behaviour and purpose of the function), anyway let me give you a hint: try using String replace function which takes two parameter "".replace(string to be replaced, string to replace for) Also a traversing over the values content will be useful as well.

Hope that helps. Now try it out :)

Aaron HARPT
Aaron HARPT
19,845 Points
Aaron HARPT
Aaron HARPT
19,845 Points

Mr. Jamal- Attached is my current version of the challenge, although I still cannot figure it out. Any more help that you could give me would be greatly appreciated.

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 :)";

utilitites.js

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


module.exports.merge = merge;