Ekene Agunechemba

Imagine you’re a word detective, holding three special magnifying glasses. Each glass helps you find hidden words or letters inside sentences — but each one works a little differently.

Today, we’ll meet our three heroes:

  • 🕵️ .test() — the quick yes/no detective
  • 🧠 .exec() — the deep-diving investigator
  • 🔍 .match() — the friendly helper that works from the string side

Ready? Let’s investigate! 🚀

🧪 1. .test() – “Is it there?”

Sometimes, you just want a simple answer: 👉 “Does this word appear in the sentence or not?”

That’s where .test() comes in!

var re = /cat/;
console.log(re.test("The cat is here"));  // true
console.log(re.test("No animal here"));   // false

.test() gives you a boolean:

  • true → if it finds a match
  • false → if it doesn’t

It’s the quickest of the three — no extra info, no fuss. Think of it like asking a guard: “Do you see a cat here?” He simply nods yes or shakes his head no. 🐈

📦 2. .exec() – “Tell me everything!”

Now, let’s say you don’t just want to know if the word is there — you also want to know where it was found and what part matched.

That’s what .exec() does. It gives you a whole report!

var re = /c(at)/;
var result = re.exec("The cat is here");

console.log(result[0]);      // "cat"  → the full match
console.log(result[1]);      // "at"   → captured group
console.log(result.index);   // 4      → position in the sentence

See how .exec() gives details? It’s like a detective who brings back:

“I found the word ‘cat’ at position 4, and I also noticed the letters ‘at’ inside it!”

It even works beautifully with loops when used with /g for global searches. It’s precise, methodical, and very detailed — perfect for pattern detectives.

🔁 3. .match() – “Search it from the string side!”

Finally, .match() is a bit like .exec() — but instead of being called from the regex, it’s called from the string itself!

Let’s see it in action:

var sentence = "The cat is here";
var result = sentence.match(/cat/);

console.log(result[0]); // "cat"

Nice and simple! But when you want to find all matches, you can use the g flag:

var str = "cat, bat, hat";
console.log(str.match(/at/g));  // ["at", "at", "at"]

So .match() is your go-to tool when you just want a list of all the matches quickly.

📚 Summary – The Detective Trio

🔍 Goal 🧰 Tool to Use 🪄 What It Returns
Just check if there’s a match .test() true or false
Get full match info and groups .exec() Array with full match + details
Find matches from a string easily .match() Single match or array of matches

Each one is powerful — but the real magic happens when you know which to use when! 🌟

💡 Quick Analogy

Imagine you’re at a treasure hunt:

  • .test() just says, “Yes, treasure is here!”
  • .exec() digs it up and gives you the coordinates!
  • .match() lists all treasures in one glance!

That’s how regex turns you into a text-finding superhero! 🦸‍♀️🦸‍♂️

🧩 Review – Fill in the Gaps

Now, let’s check how sharp your detective skills are! Fill in the missing words to complete these sentences. ✍️

  1. The .test() method returns either ______ or ______.
  2. .exec() provides detailed match information like the full match, captured groups, and the match ______.
  3. To search for all matches, you add the ______ flag to your regular expression.
  4. The method .match() is called on the ______, not the regex.
  5. .test() is best when you only need a simple ______ or ______ answer.
  6. The captured parts of a regex can be accessed inside .exec() using bracket notation like result[______].
  7. When .exec() finds a match, it returns an array; if no match, it returns ______.
  8. The .match() method can return an ______ of all found matches when used with the global flag.
  9. The property result.index tells you where the ______ started in the string.
  10. All three — .test(), .exec(), and .match() — are used to ______ for patterns inside strings.
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