ternary

The ternary operator (also known as the conditional operator) is a concise way to write simple conditional expressions. It uses the syntax condition ? valueIfTrue : valueIfFalse and returns one of two values based on a boolean condition.

Basic Ternary Operator

Simple conditional value assignment:

age = 20
status = age >= 18 ? "adult" : "minor"
println(status)  // "adult"

// Traditional if-else equivalent
if (age >= 18) {
    status = "adult"
} else {
    status = "minor"
}

Ternary with Different Data Types

Return different types of values:

// String values
isLoggedIn = true
greeting = isLoggedIn ? "Welcome back!" : "Please log in"

// Number values
quantity = 5
discount = quantity > 10 ? 0.1 : 0.05

// Boolean values
hasPermission = false
canAccess = hasPermission ? true : false

// Null values
user = getUser()
displayName = user != null ? user.name : "Guest"

Ternary in Variable Assignment

Use ternary for conditional assignments:

score = 85
grade = score >= 90 ? "A" : 
        score >= 80 ? "B" : 
        score >= 70 ? "C" : 
        score >= 60 ? "D" : "F"

// Price calculation
isPremium = true
basePrice = 100
finalPrice = isPremium ? basePrice * 0.9 : basePrice

// Default values
config = getConfig()
timeout = config != null ? config.timeout : 5000

Ternary in Function Arguments

Pass conditional values to functions:

level = 5
message = formatMessage(
    level > 3 ? "High priority" : "Normal priority",
    level > 7 ? "urgent" : "standard"
)

// Function calls
user = getCurrentUser()
logActivity(
    user != null ? user.id : "anonymous",
    user != null ? user.name : "Unknown User"
)

Ternary in Return Statements

Return conditional values from functions:

soul getAccessLevel(user) {
    return user.isAdmin ? "admin" : 
           user.isModerator ? "moderator" : "user"
}

soul calculateTax(amount, region) {
    return region == "NY" ? amount * 0.08 : 
           region == "CA" ? amount * 0.075 : 
           amount * 0.05
}

soul isValidEmail(email) {
    return email != null && email.contains("@") ? true : false
}

Nested Ternary Operators

Chain multiple ternary operators:

temperature = 75
weather = temperature > 80 ? "hot" : 
          temperature > 60 ? "warm" : 
          temperature > 40 ? "cool" : "cold"

// User role determination
user = getUser()
role = user == null ? "guest" : 
       user.isAdmin ? "admin" : 
       user.isModerator ? "moderator" : "user"

// Grade calculation
score = 88
letterGrade = score >= 90 ? "A" : 
              score >= 80 ? "B" : 
              score >= 70 ? "C" : 
              score >= 60 ? "D" : "F"

Ternary with Object Properties

Use ternary for object property access:

user = {
    "name": "Alice",
    "profile": {
        "avatar": "avatar.jpg"
    }
}

// Safe property access
userName = user != null ? user.name : "Unknown"
avatar = user != null && user.profile != null ? user.profile.avatar : "default.jpg"

// Object creation with ternary
person = {
    "name": name,
    "age": age != null ? age : 0,
    "isActive": isActive != null ? isActive : true
}

Ternary in Array Operations

Use ternary with arrays:

numbers = [1, 2, 3, 4, 5]
results = []

for (num in numbers) {
    // Add conditional values to array
    results.push(num > 3 ? "high" : "low")
}

// Array filtering with ternary
items = getItems()
filtered = items != null ? items.filter(isValid) : []

// Array access with ternary
firstItem = items.length() > 0 ? items[0] : null

Ternary with Method Calls

Call different methods based on conditions:

user = getCurrentUser()
message = user != null ? user.getWelcomeMessage() : getGuestMessage()

// Method chaining with ternary
result = data != null ? data.process().format() : getDefaultResult()

// Conditional method calls
logger = getLogger()
shouldLog = isDebugMode()
logMessage = shouldLog ? logger.debug("Debug info") : logger.info("Info")

Ternary in String Operations

Use ternary for string manipulation:

name = "alice"
displayName = name != null ? name.toUpperCase() : "UNKNOWN"

// String concatenation
firstName = "John"
lastName = "Doe"
fullName = firstName != null && lastName != null ? 
           firstName + " " + lastName : 
           "Name not available"

// String formatting
count = 5
message = "You have " + count + " " + (count == 1 ? "item" : "items")

Ternary with Calculations

Use ternary in mathematical expressions:

balance = 1000
withdrawAmount = 200
newBalance = balance >= withdrawAmount ? 
             balance - withdrawAmount : 
             balance

// Discount calculation
quantity = 15
unitPrice = 10
total = quantity * unitPrice
discount = quantity > 10 ? total * 0.1 : 0
finalTotal = total - discount

// Min/Max operations
a = 5
b = 8
maximum = a > b ? a : b
minimum = a < b ? a : b

Ternary with Error Handling

Handle simple error cases:

// Input validation
input = getUserInput()
processedInput = input != null && input != "" ? input.trim() : null

// Error messages
errorCode = getErrorCode()
errorMessage = errorCode == 404 ? "Not found" : 
               errorCode == 500 ? "Server error" : 
               "Unknown error"

// Safe operations
divisor = 5
result = divisor != 0 ? 100 / divisor : 0

Ternary Performance Considerations

Optimize ternary usage:

// Good - simple conditions
isActive = user != null ? user.isActive : false

// Avoid - complex expressions in ternary
// result = complexFunction() ? expensiveOperation() : anotherExpensiveOperation()

// Better - evaluate once
shouldProcess = complexFunction()
result = shouldProcess ? expensiveOperation() : anotherExpensiveOperation()

Ternary vs If-Else

When to use ternary vs if-else:

// Use ternary for simple value assignment
status = isOnline ? "online" : "offline"

// Use if-else for complex logic
if (user.isAdmin) {
    setupAdminDashboard()
    logAdminAccess()
    sendAdminNotification()
} else {
    setupUserDashboard()
    logUserAccess()
}

// Use ternary for inline conditions
message = "Hello " + (user != null ? user.name : "Guest") + "!"

// Use if-else for multiple statements
if (user != null) {
    welcomeUser(user)
    logUserActivity(user)
    updateLastSeen(user)
} else {
    showLoginForm()
    trackAnonymousVisit()
}

Best Practices

Keep it simple: Use ternary for simple conditions only
Avoid deep nesting: More than 2-3 levels becomes hard to read
Use parentheses: Clarify precedence with parentheses
Consider readability: If-else might be clearer for complex logic
Handle null values: Always consider null cases

// Good - simple and clear
age = 25
category = age >= 18 ? "adult" : "minor"

// Good - with parentheses for clarity
result = (score >= 90) ? "excellent" : (score >= 70) ? "good" : "needs improvement"

// Avoid - too complex
// complicated = condition1 ? (condition2 ? value1 : (condition3 ? value2 : value3)) : value4

// Better - break down complex ternary
if (condition1) {
    result = condition2 ? value1 : (condition3 ? value2 : value3)
} else {
    result = value4
}

// Good - safe null handling
user = getUser()
welcomeMessage = user != null ? "Hello " + user.name : "Welcome, Guest"

// Better - comprehensive null handling
user = getUser()
userName = (user != null && user.name != null) ? user.name : "Guest"
welcomeMessage = "Hello " + userName

The ternary operator is a powerful tool for writing concise conditional expressions. Use it for simple value assignments and inline conditions, but prefer if-else statements for complex logic and multiple statements.

CLI Usage

Modules

Syntaxes

ternary

ternary

Basic Ternary Operator

Ternary with Different Data Types

Ternary in Variable Assignment

Ternary in Function Arguments

Ternary in Return Statements

Nested Ternary Operators

Ternary with Object Properties

Ternary in Array Operations

Ternary with Method Calls

Ternary in String Operations

Ternary with Calculations

Ternary with Error Handling

Ternary Performance Considerations

Ternary vs If-Else

Best Practices

​ternary

​Basic Ternary Operator

​Ternary with Different Data Types

​Ternary in Variable Assignment

​Ternary in Function Arguments

​Ternary in Return Statements

​Nested Ternary Operators

​Ternary with Object Properties

​Ternary in Array Operations

​Ternary with Method Calls

​Ternary in String Operations

​Ternary with Calculations

​Ternary with Error Handling

​Ternary Performance Considerations

​Ternary vs If-Else

​Best Practices

ternary

Basic Ternary Operator

Ternary with Different Data Types

Ternary in Variable Assignment

Ternary in Function Arguments

Ternary in Return Statements

Nested Ternary Operators

Ternary with Object Properties

Ternary in Array Operations

Ternary with Method Calls

Ternary in String Operations

Ternary with Calculations

Ternary with Error Handling

Ternary Performance Considerations

Ternary vs If-Else

Best Practices