docs: Call () 'unit' instead of 'nil'

This commit is contained in:
Brian Anderson 2012-10-03 20:06:24 -07:00
parent d0893fe219
commit c8ee49a5b6
2 changed files with 8 additions and 8 deletions

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@ -246,7 +246,7 @@ define a struct type with the same contents, and declare
`gettimeofday` to take a pointer to such a struct.
The second argument to `gettimeofday` (the time zone) is not used by
this program, so it simply declares it to be a pointer to the nil
this program, so it simply declares it to be a pointer to the unit
type. Since all null pointers have the same representation regardless of
their referent type, this is safe.

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@ -294,11 +294,11 @@ are not semicolons in the blocks of the second snippet. This is
important; the lack of a semicolon after the last statement in a
braced block gives the whole block the value of that last expression.
Put another way, the semicolon in Rust *ignores the value of an expression*.
Thus, if the branches of the `if` had looked like `{ 4; }`, the above example
would simply assign `()` (nil or void) to `price`. But without the semicolon, each
branch has a different value, and `price` gets the value of the branch that
was taken.
Put another way, the semicolon in Rust *ignores the value of an
expression*. Thus, if the branches of the `if` had looked like `{ 4; }`,
the above example would simply assign `()` (unit or void) to
`price`. But without the semicolon, each branch has a different value,
and `price` gets the value of the branch that was taken.
In short, everything that's not a declaration (`let` for variables,
`fn` for functions, et cetera) is an expression, including function bodies.
@ -839,7 +839,7 @@ fn point_from_direction(dir: Direction) -> Point {
Tuples in Rust behave exactly like structs, except that their fields
do not have names (and can thus not be accessed with dot notation).
Tuples can have any arity except for 0 or 1 (though you may consider
nil, `()`, as the empty tuple if you like).
unit, `()`, as the empty tuple if you like).
~~~~
let mytup: (int, int, float) = (10, 20, 30.0);
@ -891,7 +891,7 @@ fn int_to_str(i: int) -> ~str {
}
~~~~
Functions that do not return a value are said to return nil, `()`,
Functions that do not return a value are said to return unit, `()`,
and both the return type and the return value may be omitted from
the definition. The following two functions are equivalent.