Function format_xml::spaced_comma_set

pub fn spaced_comma_set<I: IntoIterator>(
    iterable: I
) -> SpacedSet<impl Clone + Iterator<Item = CommaFmt<I::Item>>> where
    I::IntoIter: Clone, 

Formats an iterable with spaces of comma formatted items.

let data = [(1.0, 2.0), (13.0, 42.0), (-5.0, 100.0)];
let result = format_xml::xml! {
	<polygon points={format_xml::spaced_comma_set(data.iter().cloned())} />
}.to_string();
assert_eq!(result, r#"<polygon points="1,2 13,42 -5,100 " />"#);