Isolate nested sass map into new map - sass

Question

How can I isolate nested sass map into a new map? For example I have sass map like this:
$susy-setting: (
s: (
'columns': 4,
'gutters': 30px,
),
m: (
'columns': 8,
'gutters': 30px,
),
l: (
'columns': 12,
'gutters': 30px,
)
);
Then I need to isolate each map inside after the loop, because my other mixin need map for its parameter.
#each $setting in $susy-setting{
#include susy-settings-block($setting) { // This mixin need map
#for $i from 1 through map-get($setting, 'columns') {
#content;
}
}
}

Answer 1

To answer your primary question, you'll need to get both the key and value in your loop: #each $size, $setting in $susy-setting. The $size variable will store the key (e.g. s, m, l) while the $setting variable stores the map value assigned to that key.
EDIT: I saw your comment on my gist, which provides a bit more context. Try this:
#mixin susy-settings-block(
$name,
$config: $susy-settings
) {
// store the old settings
$global: $susy;
// Get the new settings by name
$new: map-get($config, $name);
// apply the new settings
$susy: map-merge($susy, $new) !global;
// allow nested styles, using new settings
#content;
// return to the initial settings
$susy: $global !global;
}