Exporting Namespace Content in TypeScript

TypeScript Modules and Namespaces : Exercise-8 with Solution

Write a TypeScript namespace called Logger that contains a function logMessage. Export the Logger namespace and import it into a different TypeScript file to use the logMessage function for logging messages.

Sample Solution:

TypeScript Code:

main.ts

import Logger = require('./Logger'); // Import the Logger namespace

Logger.logMessage("This is a log message."); 

Logger.ts

namespace Logger {
  export function logMessage(message: string) {
    console.log('[Info] ${message}');
  }
}

export = Logger; // Export the Logger namespace

Explanation:

In the exercise above -

• "Logger.ts" is a TypeScript namespace that contains a function "logMessage()". This function logs messages with a "[Info]" prefix to the console.
• In "main.ts", we import the "Logger" namespace using the 'require' syntax. This is the way to import modules using CommonJS style.
• Finally, we use the "logMessage()" function from the "Logger" namespace to log a message in the console.

Output:

[Info] This is a log message.

TypeScript Editor:

See the Pen TypeScript by w3resource (@w3resource) on CodePen.

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