Formatting
We've seen that formatting is specified via a format string:
format!("{}", foo)->"3735928559"format!("0x{:X}", foo)->"0xDEADBEEF"format!("0o{:o}", foo)->"0o33653337357"
The same variable (foo) can be formatted differently depending on which
argument type is used: X vs o vs unspecified.
This formatting functionality is implemented via traits, and there is one trait
for each argument type. The most common formatting trait is Display, which
handles cases where the argument type is left unspecified: {} for instance.
You can view a full list of formatting traits and their argument
types in the std::fmt documentation.
Activity
Add an implementation of the fmt::Display trait for the Color struct above
so that the output displays as:
RGB (128, 255, 90) 0x80FF5A
RGB (0, 3, 254) 0x0003FE
RGB (0, 0, 0) 0x000000
Two hints if you get stuck:
- You may need to list each color more than once,
- You can pad with zeros to a width of 2 with
:0>2.