Loops

The runtime ships a foreach macro that walks the items of a list or set without you touching indexes or lengths.

#include "abscom/abs.h"

foreach

foreach (var item, var collection) {
    /* body */
}

foreach works on lists and sets. Inside the body, item is bound to each element in order. The macro expands to a for loop built on get_len_fast and get.

Example

abs_init();

var xs = range(0, 5);
foreach (var x, xs) {
    print(x);
}

/* 0 1 2 3 4 (one per line) */

Iterating a set visits each member once, in no guaranteed order (same as Python):

var s = Set();
set_add(s, v("a"));
set_add(s, v("b"));
foreach (var item, s) {
    print(item);
}

Non-iterables

foreach relies on get_len_fast, which returns 0 for anything that is not a list or set — so passing an int, string, dict, or None simply iterates zero times rather than raising an error.

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