Control Flow

// Simple if statement
if 2 > 1 {
  print("2 is greater than 1")
}

// if-else chain
if 2 < 1 {
  print("This won't print")
} else if 1 > 1 {
  print("Nor this")
} else {
  print("But this will")
}

// if expressions (return values)
let x = 10
let result = if x > 0 { "positive" } else { "non-positive" }
print(result) // "positive"

// Inline conditional
let message = if logged_in { "Welcome back!" } else { "Please log in" }

// Inclusive range (1 to 5)
for i in 1..=5 {
  print(` > {i}`)
}
// Output: 1, 2, 3, 4, 5

// Exclusive range (1 to 4)
for i in 1..5 {
  print(` > {i}`)
}
// Output: 1, 2, 3, 4

// Character ranges
for c in 'a'..='z' {
  print(` > {c}`)
}
// Output: a, b, c, ..., z

// Iterate over vector elements
let numbers = [1, 2, 3, 4, 5]
for num in numbers {
  print(`Number: {num}`)
}

// Basic while loop
let mut i = 0
while i < 10 {
  print(`Count: {i}`)
  i += 1
}

// While with complex condition
let mut attempts = 0
let mut success = false

while attempts < 3 && !success {
  success = try_operation()
  attempts += 1
}

// Infinite loop with break
let mut counter = 0
while true {
  counter += 1
  if counter > 100 {
      break
  }
}

// Using break and continue
for i in 1..=100 {
  if i == 50 {
      break // Exit the loop completely
  }

  if i % 2 == 0 {
      continue // Skip to next iteration
  }

  print(i) // Only prints odd numbers up to 49
}

// Early return from function
fun find_first_even(numbers: Int[]): Option<Int> {
  for num in numbers {
      if num % 2 == 0 {
          return Some(num)
      }
  }
  None // No even number found
}

// Guard clauses
fun process_user(user: User): Result<String, String> {
  if !user.is_active {
      return Err("User is not active")
  }

  if user.age < 18 {
      return Err("User must be 18 or older")
  }

  // Main processing logic here
  Ok(`Processing user: {user.name}`)
}

// Avoid deep nesting
// Bad:
if condition1 {
  if condition2 {
      if condition3 {
          // deeply nested code
      }
  }
}

// Better: Combine conditions
if condition1 && condition2 && condition3 {
  // main logic here
}