Match All Letters and Numbers - Why doesn't the example work when used?

JavaScript
1

Tell us what’s happening:
I don’t understand why using the example that was given does not work like it does in the example.
example shows that /\w+/ should work but it does not. or at least that was not what passes the test.

whats i coded below is what passed the test.
Your code so far

let quoteSample = "The five boxing wizards jump quickly.";
let alphabetRegexV2 = /[\w*]/gi; // Change this line
let result = quoteSample.match(alphabetRegexV2).length;

Your browser information:

User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/67.0.3396.87 Safari/537.36.

Link to the challenge:
https://learn.freecodecamp.org/javascript-algorithms-and-data-structures/regular-expressions/match-all-letters-and-numbers

2

The working one is the /\w/gi .

If you print to the console what you found, you will see that the result is 6 for the test sentence. Meaning they will select all the words. If you remove the brackets, it will give the solution.

3

/\w+/
This reads one or more characters in [a-zA-Z0-9_] . In other words, this means a single word. So, it matches with "The" in the example.

/\w+/g
This will apply previous regex across the string. So, the result is an array containing all the words.
["The", "five", "boxing", "wizards", "jump", "quickly"]
As you see, this means count all the words in a string; this is obviously not what the exercise is asking for.

Now, what you did is sort of incorrect because of the * in the character class [].
When you put that in brackets, it doesn’t mean match zero or more anymore; it literally means match with * character.

So, your regex translates to this
/[a-zA-Z0-9_*]/gi
Notice the i modifier is redundant because \w already includes uppercase and lowercase alphabets.
Also, notice that because you’ve added * it will count more than the set of alphanumeric characters.

This is a fixed version of your regex
/[\w]/g
Now, I will explain why this works.

/[\w]/ will match any single alphanumeric character in a string.
/[\w]/g applies above regex across the string, which means all alphanumeric characters in the string.

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