Language Features

Types and literals

Turf has built-in types:

• int
• double
• bool
• string
• void (for functions that don’t return a value)

Examples:

int a = 42
double b = 3.14
bool ok = true
string msg = "hello"

Comments

Use // for single-line comments:

// This is a comment
printline("ok")

Variables and assignment

Variables are declared with an explicit type:

int x = 5
double pi = 3.14
bool flag = true
string name = "Turf"

Reassignment uses =:

x = x + 1

Turf also supports compound assignment and increments:

x += 1
x -= 1
x *= 2
x /= 2
x++
x--

Operators

Arithmetic:

• + - * /
• % (modulo)
• ^ (exponentiation)

Comparison:

• < > <= >=
• == !=

Boolean logic:

• &&
• ||

Unary negation:

int a = -5
double b = -3.14

Control flow

If / elseif / else

Statement-like form:

int x = 9

if x > 10 {
  printline("big")
} elseif x > 5 {
  printline("medium")
} else {
  printline("small")
}

if is also an expression (it evaluates to a value), so you can assign it:

int a = 10
int b = 20
int m = if a > b then a else b
printline(m)

You can also use block branches for expression form:

int m2 = if a > b { a } else { b }

While

int i = 0
while i < 5 {
  i = i + 1
}

Inside loops:

• break exits the loop
• continue jumps to the next iteration

For ranges

For loops use this shape:

for i in 0..n step <step> {
  // body
}

Key points:

• The range end is exclusive: the loop condition is i < end (or i > end when stepping downward).
• step is typically one of:
  • i += 1
  • i++
  • i--

Example:

int sum = 0
for i in 1..10 step i += 1 {
  sum = sum + i
}
printline(sum)

Functions

Define a function with fn, a return type, a name, and typed parameters:

fn int add(int a, int b) {
  return a + b
}

int result = add(3, 7)
printline(result)

Void functions:

fn void do_something(int x) {
  if x > 0 {
    printline(x)
  } else {
    printline(0)
  }
}

Arrays

Arrays are fixed-size and have an element type:

int[5] nums
nums[0] = 10
nums[1] = 20
printline(nums[0])

Arrays can also be initialized with a list:

int[3] primes = [2, 3, 5]
printline(primes[2])

Read/write elements with arr[index]:

nums[i] = nums[i] * 2

Get the size with .length:

printline(nums.length)

Built-in functions

Turf includes a few built-ins:

• print(x) prints without a newline
• printline(x) prints with a newline
• typeof(expr) returns the type name as a string
• lengthof("...") returns the number of characters as an int

Example:

int x = 10
print("typeof(x): ")
printline(typeof(x))

printline(lengthof("hello"))

Type casting

Explicit casts use int(...), double(...), and string(...):

int a = int("100")
double b = double(42)
string s = string(true)
printline(a)
printline(b)
printline(s)