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JavaScript Build a Simple Dynamic Site with Node.js Creating a Basic Template Engine in Node.js Binding Values

Routine Poutine
Routine Poutine
26,050 Points
Posted by Routine Poutine
Routine Poutine
26,050 Points

Why are "%%" used for a placeholder and where does this syntax come from?

Hi,

I'm confused about the use of %% for placeholders. Where are they in the JavaScript documentation -- or Nodejs documentation?

Best,

Matt

1 Answer

Darryl Mah
Darryl Mah
5,492 Points
Darryl Mah
Darryl Mah
5,492 Points

Hello Matt, The choice of the %% placeholders is more or less up to you, you'll just want to avoid characters that will escape from the string. The logic they're going with here is to use the .replace() method on a String. https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/replace

var p = 'The quick brown fox jumps over the lazy dog. If the %dog% reacted, was it really lazy?';

console.log(p.replace('%dog%', 'monkey')); // expected output: "The quick brown fox jumps over the lazy monkey. If the monkey reacted, was it really lazy?"

hope this helps :)