Iterating with For Loops

Basic Usage

Haxe does not use traditional C-Style for loops, instead, for loops follow the following structure:

for (item in iterable) {
  Engine.log(item)
}

The iterable value which comes in one of three forms:

Iterating Through Arrays

Arrays are likely to be the most common iterator

var list = ["apple", "pear", "banana"];
for (item in list) {
  Engine.log(item); // The item variable is accessible in this block
}
// apple
// pear
// banana

Iterating Through Number Ranges

In some cases you might just need to run through a range of numbers but the data you're operating on isn't an iterable, or maybe you just want to generate a numbered sequence:

This is a basic for loop using iterators:

for (i in 0...10) {
	Engine.log(i); 
} // Prints 0 to 9

If you wanted to iterate through all characters in a string:

var greeting = "HeyGuys";
for (charIndex in 0...(greeting.length)) {
	Engine.log(string.charAt(charIndex)); 
} // Prints all the characters line by line
  // H
  // e
  // y
  // G
  // u
  // y
  // s

Using Engine.forEach and Engine.forCount

When developing in fraytools you may notice that you don't get proper completion when using regular for loops as of the time of writing.

So for iterating through items with decent completion you can use Engine.forEach and Engine.forCount

I'd also recommend taking a look at Functions since that's very relevant here.

Engine.forEach

General Structure is

Engine.forEach(numberOfItems, function (item,index) {
    // Function Body here accessing item or index
}, []);

var list = ["apple", "pear", "banana"];
Engine.forEach(list, function (item:String , idx:Int) {
  Engine.log(item); // The item variable is accessible in this block
  Engine.log(idx); // Could also access the array index

},[]);
// apple
// 0
// pear
// 1
// banana
// 2

Engine.forCount

The general structure is

Engine.forCount(numberOfItems, function (index) {
    // Function Body here
}, []);

Engine.forCount(10, function (i:Int) {
    Engine.log(i);
    return true;
}, []); // Prints 0 to 9

And Similarly for a string:

var greeting = "HeyGuys";

Engine.forCount(greeting.length, function (i:Int) {
	Engine.log(string.charAt(charIndex)); 
}, []); 
// Prints all the characters line by line
  // H
  // e
  // y
  // G
  // u
  // y
  // s