Variables & Types

Variable Declaration

Haira uses type inference — no explicit type annotations needed for local variables:

name = "Haira"        // string
age = 1               // int
pi = 3.14             // float
active = true         // bool
items = [1, 2, 3]     // []int
data = {"key": "val"} // map[string]string

Variables are mutable by default. Reassignment uses the same = syntax:

count = 0
count = count + 1

Primitive Types

Type	Description	Example
int	Integer	42
float	Floating point	3.14
string	UTF-8 string	"hello"
bool	Boolean	true, false
nil	Null value	nil

Compound Types

Lists

numbers = [1, 2, 3, 4, 5]
names = ["Alice", "Bob"]

// Access by index
first = numbers[0]

// List methods
numbers = append(numbers, 6)
length = len(numbers)

Maps

config = {
    "host": "localhost",
    "port": "8080"
}

// Access
host = config["host"]

// Add/update
config["debug"] = "true"

Strings

Strings use double quotes with ${expr} interpolation:

name = "World"
greeting = "Hello, ${name}!"

// Multi-line with triple quotes
description = """
This is a multi-line string.
It preserves line breaks.
"""

String Operations

import "string"

text = "Hello, World!"
upper = string.to_upper(text)       // "HELLO, WORLD!"
lower = string.to_lower(text)       // "hello, world!"
contains = string.contains(text, "World")  // true
parts = string.split(text, ", ")    // ["Hello", "World!"]

Type Aliases

Define type aliases with the type keyword:

type UserID = int
type Email = string

Nil and Error Handling

Functions that can fail return a value and an error:

result, err = some_operation()
if err != nil {
    io.println("Error: ${err}")
}

See Error Handling for the complete error handling guide.

Compound Assignment

x = 10
x += 5   // x = 15
x -= 3   // x = 12
x *= 2   // x = 24
x /= 4   // x = 6

Bitwise Operators

a = 0b1010
b = 0b1100

c = a & b    // AND: 0b1000
d = a | b    // OR:  0b1110
e = a ^ b    // XOR: 0b0110
f = ~a       // NOT
g = a << 2   // Left shift
h = a >> 1   // Right shift