Types

This guide covers the data types available in Tx3 and how to use them.

Built-in Types

Integer (Int)

// Integer literals
123
-456
0

• Signed integer type
• Used for quantities, timestamps, etc.
• Supports basic arithmetic operations

Boolean (Bool)

// Boolean literals
true
false

• Logical values
• Used in conditions and flags
• Supports logical operations

Bytes (Bytes)

// Hex string literals
0x"deadbeef"
0x"1234"

• Raw byte data
• Used for addresses, hashes, etc.
• Represented as hex strings

String (String)

// String literals
"hello"
"world"

• Text data
• Used for names, messages, etc.
• UTF-8 encoded

Asset Types

Native Asset (Ada)

// ADA literals
Ada(1)  // 1 ADA
Lovelace(500000)   // 0.5 ADA

• Native blockchain currency
• Basic unit operations

Custom Assets

// Asset definition
asset MyToken = 0xABCDEF123.MYTOKEN;

// Asset literals
MyToken(100)

• User-defined tokens
• Requires policy ID and name
• Supports basic arithmetic

Custom Types

Records

// Record definition
type State {
    lock_until: Int,
    owner: Bytes,
    beneficiary: Bytes,
}

// Record construction
State {
    lock_until: 1234567890,
    owner: 0x"deadbeef",
    beneficiary: 0x"12345678",
}

• Named field collections
• Used for structured data
• Field access via dot notation

Variants

// Variant definition
type Result {
    Success: Int,
    Error: String,
}

// Variant construction
Result::Success(42)
Result::Error("failed")

• Tagged unions
• Used for alternative values
• Pattern matching support

Type Usage

In Parameters

tx transfer(
    amount: Int,
    recipient: Bytes,
    message: String
) {
    // ... transaction body
}

In Data Expressions

// Record construction
State {
    lock_until: 1234567890,
    owner: sender,
    beneficiary: receiver,
}

// Variant construction
Result::Success(42)

In Asset Expressions

// ADA amount
Ada(1000000)

// Custom token amount
MyToken(100)

Type Safety

Tx3 provides several type safety features:

1. Static Type Checking

   • Types are checked at compile time
   • No runtime type errors
   • Clear error messages

2. Type Inference

   • Types can be inferred from context
   • Different semantics for Data Expressions and Asset Expressions
   • Reduces type annotations
   • Maintains type safety

3. Type Constraints

   • Custom validation rules
   • Range checks
   • Format validation