lua 7

Chapter 7 — Strings (📝 Working with Text)

If numbers are for math, strings are for words.

Almost every app uses strings.

• User names

• Passwords

• Chat messages

• Emails

• Search bars

• File names

• URLs

If it looks like text, it's probably a string.

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🎯 Mission

Imagine you're making WhatsApp.

A user sends:

Hello!

That's a string.

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🟢 LEVEL 1 — Survival

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Q1

Which of these is a string?

A)

100

B)

true

C)

"Hello"

D)

nil

✅ Answer: C

💡 Text inside quotes is a string.

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Q2

Which is NOT a string?

A)

"Lua"

B)

"123"

C)

123

D)

"Hi"

✅ Answer: C

💡 No quotes = number.

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Q3

name = "Pramod"

print(name)

Output?

A)

Pramod

B)

name

C)

"Pramod"

D) Error

✅ Answer: A

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Q4

Which is valid?

A)

city = Bangalore

B)

city = "Bangalore"

C)

city = Bangalore()

D)

city = {}

✅ Answer: B

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Q5

What are quotes (" ") mainly used for?

A) Numbers

B) Strings

C) Tables

D) Loops

✅ Answer: B

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Q6

print("Lua")

Output?

A)

Lua

B)

"Lua"

C) Error

D) nil

✅ Answer: A

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🟡 LEVEL 2 — Think Like a Programmer

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Q7

first = "Pramod"
last = "Tiwari"

print(first .. last)

Output?

A)

PramodTiwari

B)

Pramod Tiwari

C)

Pramod..Tiwari

D) Error

✅ Answer: A

💡 .. joins strings.

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Q8

first = "Pramod"
last = "Tiwari"

print(first .. " " .. last)

Output?

A)

Pramod Tiwari

B)

PramodTiwari

C)

Pramod..Tiwari

D) Error

✅ Answer: A

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Q9

Which operator joins strings?

A)

+

B)

&

C)

..

D)

*

✅ Answer: C

⚠️ Beginners often try +. Lua uses ...

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Q10

print("Hello" .. " World")

Output?

A)

Hello World

B)

HelloWorld

C) Error

D)

World Hello

✅ Answer: A

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Q11

name = "Lua"

print(#name)

Output?

A) 2

B) 3

C) 4

D) Error

✅ Answer: B

💡 # gives the length.

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Q12

print(#"Programming")

How many characters?

A) 9

B) 10

C) 11

D) 12

✅ Answer: C

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🟠 LEVEL 3 — Real-Life Programming

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Q13

A website shows:

Welcome Pramod

Best code?

A)

print("Welcome")
print(name)

B)

print("Welcome " .. name)

C)

print(name + "Welcome")

D)

print(name)

✅ Answer: B

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Q14

You want:

Score: 100

Best approach?

A)

print("Score: " .. score)

B)

print(score + "Score")

C)

print(score)

D)

print("Score")

✅ Answer: A

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Q15

A game says:

Game Over

This is...

A) Number

B) String

C) Boolean

D) Table

✅ Answer: B

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Q16

You're building a login screen.

Username should be stored as...

A) Number

B) String

C) Boolean

D) Loop

✅ Answer: B

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Q17

A chatbot receives messages.

Each message is...

A) String

B) Table

C) Function

D) Number

✅ Answer: A

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Q18

A filename like:

photo.jpg

is usually stored as...

A) Number

B) String

C) Boolean

D) Loop

✅ Answer: B

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🔴 LEVEL 4 — Bug Hunter

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Q19

name = Pramod

Problem?

A) Missing quotes

B) Missing loop

C) Missing table

D) Nothing

✅ Answer: A

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Q20

print("Hello" + "World")

Problem?

A) Should use ..

B) Missing if

C) Missing end

D) Nothing

✅ Answer: A

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Q21

name = "Lua"

print(name + 1)

Problem?

A) Nothing

B) Can't add text and number with +

C) Missing quotes

D) Missing loop

✅ Answer: B

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Q22

word = "Cat"

print(#word)

Output?

A) 2

B) 3

C) 4

D) Error

✅ Answer: B

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Q23

print("Age: " .. 20)

Output?

A)

Age: 20

B) Error

C)

20Age

D)

Age:

✅ Answer: A

💡 Lua automatically converts the number when concatenating with ...

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Q24

Which is correct?

A)

print("Hello" .. "Lua")

B)

print("Hello" + "Lua")

C)

print("Hello" * "Lua")

D)

print("Hello" & "Lua")

✅ Answer: A

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🟣 LEVEL 5 — Boss Battle 👑

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Q25

How do you join two strings in Lua?

A)

+

B)

..

C)

&

D)

=

✅ Answer: B

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Q26

How do you find the length of a string?

A)

length(name)

B)

#name

C)

size(name)

D)

count(name)

✅ Answer: B

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Q27

first = "Chat"
second = "GPT"

print(first .. second)

Output?

A)

Chat GPT

B)

ChatGPT

C)

GPTChat

D) Error

✅ Answer: B

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Q28

Which is most likely to be a string?

A) Health

B) Coins

C) Email Address

D) Player Level

✅ Answer: C

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Q29

Which operator is used most often with strings?

A)

+

B)

-

C)

..

D)

/

✅ Answer: C

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Q30 — Final Boss 🏆

You're building a game.

You want to display:

Welcome Pramod!
Level: 25
Coins: 1000

What's your first thought?

A) Store everything as numbers.

B) Combine strings with variables using ...

C) Use only loops.

D) Use only tables.

✅ Answer: B

💡 Almost every app you use creates messages by joining text with variables. That's why string concatenation (..) is one of the most frequently used Lua features.

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🧠 Pareto Cheat Sheet

Situation	Use
Text	"Hello"
Join strings	..
Length of string	#text
Store a name	"Pramod"
Store an email	"abc@gmail.com"
Display message	"Welcome " .. name

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🏆 The 80/20 Rule for Strings

If you remember only three things from this chapter, remember these:

1. Text goes inside quotes → "Hello"

2. Join text with .. → "Hi " .. name

3. Get length with # → #name

Those three cover most of the string operations you'll use in beginner and intermediate Lua programs.