Loops (compile-time)
Sometimes you need to do things multiple times; an especially powerful tool at compile time. There are two primary types of iteration in MCCompiled:
Repeating N Times
Repeating a statement/set of statements some number of times is useful in lots of cases. As such, MCCompiled's $repeat command is a powerful and simple choice for doing this. This page discusses the preprocessor version of the command, which runs exclusively at compile time. See runtime repeat here.
An example is shown here summoning 10 zombies at the given coordinates.
Current Iteration
Sometimes it's also necessary to know what iteration the repeat is currently on. For this, you can specify the second parameter, which is the identifier of the preprocessor variable to store the current iteration in.
When iterating a single digit like this, the variable always begins at zero and ends at the ending number minus one. In the following example, the identifier xOffset is used, and then its value is used to offset where each zombie is spawned. xOffset begins at 0, and ends at 9, covering 10 total digits.
Iterating Over Ranges
When you want an iteration to have an upper and lower bound, you can use a range as an input rather than a single number. Like in regular Minecraft, ranges are always inclusive; so 2..5 includes the indices 2, 3, 4, 5.
Iterating over Arrays
When you want to iterate over the elements in an object but don't care about the location it's at, the $iterate command is the best choice. The syntax of the iterate command is $iterate [object] [id: current]. The argument 'current' will be the name of the preprocessor variable that stores the current element in the iteration.
Preprocessor Variable Elements
The most simple iteration you can do is over the elements in a preprocessor variable. To specify a preprocessor variable, enter its identifier as the input for "object." Regardless of what's stored in the preprocessor variable, its elements are guaranteed to be iterated over (even if it contains one element).