1<===> input.scss
2@function test($from, $to) {
3    @warn 'Starting loop';
4    @for $i from $from through $to {
5      @warn 'Step #{$i}' ;
6    }
7    @warn 'Finished loop';
8    @return 100%;
9}
10body {
11    width: test(0, 1);
12    height: test(-1, 1);
13}
14<===> output.css
15body {
16  width: 100%;
17  height: 100%;
18}
19
20<===> warning
21WARNING: Starting loop
22         on line 2 of input.scss
23
24WARNING: Step 0
25         on line 4 of input.scss
26
27WARNING: Step 1
28         on line 4 of input.scss
29
30WARNING: Finished loop
31         on line 6 of input.scss
32
33WARNING: Starting loop
34         on line 2 of input.scss
35
36WARNING: Step -1
37         on line 4 of input.scss
38
39WARNING: Step 0
40         on line 4 of input.scss
41
42WARNING: Step 1
43         on line 4 of input.scss
44
45WARNING: Finished loop
46         on line 6 of input.scss
47
48<===> warning-dart-sass
49WARNING: Starting loop
50    input.scss 2:5    test()
51    input.scss 10:12  root stylesheet
52
53WARNING: Step 0
54    input.scss 4:7    test()
55    input.scss 10:12  root stylesheet
56
57WARNING: Step 1
58    input.scss 4:7    test()
59    input.scss 10:12  root stylesheet
60
61WARNING: Finished loop
62    input.scss 6:5    test()
63    input.scss 10:12  root stylesheet
64
65WARNING: Starting loop
66    input.scss 2:5    test()
67    input.scss 11:13  root stylesheet
68
69WARNING: Step -1
70    input.scss 4:7    test()
71    input.scss 11:13  root stylesheet
72
73WARNING: Step 0
74    input.scss 4:7    test()
75    input.scss 11:13  root stylesheet
76
77WARNING: Step 1
78    input.scss 4:7    test()
79    input.scss 11:13  root stylesheet
80
81WARNING: Finished loop
82    input.scss 6:5    test()
83    input.scss 11:13  root stylesheet
84