Greetings! Today, you will explore handling and manipulating strings in TypeScript, a fundamental skill in many areas of programming. Specifically, we'll learn how to identify consecutive groups of identical characters in a string. Eager to enhance your skills? Let's dive in!

In this lesson, your objective is to write a TypeScript function that accepts a string as input and identifies all consecutive groups of identical characters within it. A group is defined as a segment of the text wherein the same character is repeated consecutively.

Your function should return an array of strings. Each string will consist of the repeating character and the length of its repetition, joined by a colon (:). For example, if the input string is "aaabbcccaae", your function should output: ["a:3", "b:2", "c:3", "a:2", "e:1"].

Bear in mind that, while processing the input string, we are interested only in alphanumeric characters (i.e., alphabets and digits). Other characters present will not factor into the formation of these groups.

Ready to discover how to accomplish this task? Let's set forth!

When aiming to solve a problem, it's always crucial to first establish our scope by taking preliminary steps. First, we will initialize an empty array to store our results. We will also declare two variables, currentGroupChar and currentGroupLength, which will help us monitor the character of the current group and the length of its consecutive sequence.