Scala Loop Types

Scala provides various ways to perform iterations through loops. Understanding these loop types is essential for effective programming in Scala. Here’s a summary of the main loop types available in Scala:

1. While Loop

The while loop continues executing as long as the specified condition is true.

Key Concepts:

• The condition is evaluated before each iteration.

Syntax:

while (condition) {
    // code to be executed
}

Example:

var i = 1
while (i <= 5) {
  println(i)
  i += 1
}

Output:

1
2
3
4
5

2. Do-While Loop

The do-while loop is similar to the while loop, but it guarantees that the code inside the loop will execute at least once, as the condition is checked after the code executes.

Key Concepts:

Syntax:

do {
    // code to be executed
} while (condition)

Example:

var j = 1
do {
  println(j)
  j += 1
} while (j <= 5)

Output:

1
2
3
4
5

3. For Loop

The for loop is a versatile way to iterate over a range or a collection.

Key Concepts:

• The to keyword includes the end value, while until excludes it.

Syntax for a range:

for (i <- 1 to 5) {
    // code to be executed
}

Example:

for (k <- 1 to 5) {
  println(k)
}

Output:

1
2
3
4
5

Example with until:

for (k <- 1 until 5) {
  println(k)
}

Output:

1
2
3
4

4. For Loop with Collections

You can also use for loops to iterate over collections like lists or arrays.

Example:

val fruits = List("Apple", "Banana", "Cherry")
for (fruit <- fruits) {
  println(fruit)
}

Output:

Apple
Banana
Cherry

Conclusion

Scala offers different types of loops, each suited for various scenarios:

• While Loop: Use when the number of iterations is not predetermined.
• Do-While Loop: Use when at least one iteration is required.
• For Loop: Use for fixed iterations or when iterating over collections.

Understanding these loop types will help you write more efficient and readable Scala code!