My first coding round was a disaster. I was asked to design and implement an initial version of a templating system with substitution. I suggested using Angular's template literals, but I wasn't sure what the interviewer was looking for. I wasn't clear on what he wanted me to achieve in this coding round. I will never go for a company like Plaid.

Context

It's often useful to write HTML templates into which we can programmatically substitute variables. For example, a template might look like this:

html

or like this:

html

among other possibilities. Either way, filling the template with a statement like:

javascript const s = readTemplate() template = compile(s) template.fill({ username: "foo" })

would yield a result like:

html

Most templating engines also support conditional statements. For example:

javascript template.fill({ showWelcomeMessage: true })

would be one way to specify if the welcome message should be shown. (Yes, in this case.)

Challenge

• Pick one of the two syntax options shown above.
• Design and implement an initial version of the templating system with substitution.
• If time allows, add support for boolean conditionals to it.