➰Loops

Gauntlet supports two types of loops

For syntax of varPattern see Common placeholders throughout documentation

break and continue are supported

1. For-loops

Syntax for-loop (traditional style)

for let <varPattern> = <expr>; <terminal expr>; <expr run after every iteration> {
    <loop body>
} 

Working Example

Gauntlet

package main

import "fmt" as fmt

fun Unit main() {
  fmt.println("Counting to 10...")
  for let a = 1; a <= 10; a++ {
    fmt.println(a)
  }
  fmt.println("Done!")
}

Transpiled

package main

import fmt "fmt"

func main() {
	fmt.Println("Counting to 10...")
	for a := 1; a <= 10; a++ {
		fmt.Println(a)
		// Eliminates any 'unused variable' errors
		_ = a
	}
	fmt.Println("Done!")

}

Output

Counting to 10...
1
2
3
4
5
6
7
8
9
10
Done!

Syntax for for-loop (shorthand style)

for let <varPattern> in <iterable> {
    <loop body>
}

Working Example

Gauntlet

package main

import "fmt" as fmt

fun Unit main() {
  fmt.println("Iterating through every letter in the word 'Hello'")
  for let _, c in "Hello" {
    fmt.println((String)(c))
  }
  fmt.println("Done!")
}

Transpiled

package main

import fmt "fmt"

func main() {
	fmt.Println("Iterating through every letter in the word 'Hello'")
	for _, c := range "Hello" {
		fmt.Println(string(c))
		// Eliminates any 'unused variable' errors
		_ = c
	}
	fmt.Println("Done!")

}

Output

Iterating through every letter in the word 'Hello'
H
e
l
l
o
Done!

2. While-loops

While-loop syntax:

for <terminal expr> {
    <loop body>
}

Working Example

Gauntlet

package main

import "fmt" as fmt

fun Unit main() {
  fmt.println("The program will terminate if you say the magic word...")
  
  let magicWord = "please"
  zero String input
  
  while input != magicWord {
    fmt.println("What's the magic word?")
    fmt.scan(&input)
  }
  fmt.println("You said it!")
}

Transpiled

package main

import fmt "fmt"

func main() {
	fmt.Println("The program will terminate if you say the magic word...")
	magicWord := "please"
	var input string
	for {
		if !(input != magicWord) {
			break
		}
		fmt.Println("What's the magic word?")
		fmt.Scan(&input)
	}
	fmt.Println("You said it!")
	// Eliminates any 'unused variable' errors
	_, _ = magicWord, input

}

Output

The program will terminate if you say the magic word...
What's the magic word?
Gauntlet
What's the magic word?
Go
What's the magic word?
Life
What's the magic word?
please
You said it!