while loops are 1:1; c-style and range for-each both desugar to
a `{ var; while { body; iter; } }` block.

<<<

main = fun () {
    var i int = 0
    while i < 10 {
        i++
    }
    for j int = 0, j < 5, j++ {
        var k int = j
    }
    for r int = 0..3 {
        var s int = r
    }
}

>>>

#include "core.c"
void catskill_main(void);
void catskill_main(void) {
    integer i = 0;
    while (i < 10) {
        i = i + 1;
    }
    {
        integer j = 0;
        while (j < 5) {
            integer k = j;
            j = j + 1;
        }
    }
    {
        integer r = 0;
        while (r < 3) {
            integer s = r;
            r = r + 1;
        }
    }
}
#include "runtime.c"