12E+99_f64; // type f64
```
-##### Unit and boolean literals
+##### Boolean literals
-The _unit value_, the only value of the type that has the same name, is written
-as `()`. The two values of the boolean type are written `true` and `false`.
+The two values of the boolean type are written `true` and `false`.
### Symbols
### Tuple expressions
-Tuples are written by enclosing one or more comma-separated expressions in
+Tuples are written by enclosing zero or more comma-separated expressions in
parentheses. They are used to create [tuple-typed](#tuple-types) values.
```{.tuple}
("a", 4u, true);
```
+### Unit expressions
+
+The expression `()` denotes the _unit value_, the only value of the type with
+the same name.
+
### Structure expressions
```{.ebnf .gram}