Integers 1, floats 1.2, characters 'a', strings "abc", booleans true
and the unit type () can be expressed using literals.
Integers can, alternatively, be expressed using hexadecimal, octal or binary
notation using either of these prefixes: 0x, 0o or 0b.
Underscores can be inserted in numeric literals to improve readability, e.g.
1_000 is the same as 1000, and 0.000_001 is the same as 0.000001.
We need to tell the compiler what is the type of the literals we use. For now,
we'll use the u suffix to indicate that the literal is an unsigned integer,
and the i suffix to indicate that it's a signed integer. We'll cover the type
system in another chapter, and give more details about type
annotating literals in their own section.
The operators available and their precedence are similar to other C-like languages.