Function parse_length 

pub fn parse_length(s: &str) -> Option<Length>

Parse a length literal.

Supports:

• Absolute units: pt, mm, cm, in
• Relative units: em

Examples

parse_length("12pt") // Some(Length::from(Abs::pt(12.0)))
parse_length("1.5em") // Some(Length::from(Em::new(1.5)))