update tutorial and manual to use new impl Trait for Type
syntax
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24
doc/rust.md
24
doc/rust.md
@ -1209,7 +1209,7 @@ to pointers to the trait name, used as a type.
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~~~~
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# trait Shape { }
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# impl int: Shape { }
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# impl Shape for int { }
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# let mycircle = 0;
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let myshape: Shape = @mycircle as @Shape;
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@ -1233,7 +1233,7 @@ For example:
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trait Num {
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static pure fn from_int(n: int) -> Self;
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}
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impl float: Num {
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impl Num for float {
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static pure fn from_int(n: int) -> float { n as float }
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}
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let x: float = Num::from_int(42);
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@ -1269,8 +1269,8 @@ Likewise, supertrait methods may also be called on trait objects.
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~~~ {.xfail-test}
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# trait Shape { fn area() -> float; }
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# trait Circle : Shape { fn radius() -> float; }
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# impl int: Shape { fn area() -> float { 0.0 } }
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# impl int: Circle { fn radius() -> float { 0.0 } }
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# impl Shape for int { fn area() -> float { 0.0 } }
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# impl Circle for int { fn radius() -> float { 0.0 } }
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# let mycircle = 0;
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let mycircle: Circle = @mycircle as @Circle;
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@ -1292,7 +1292,7 @@ Implementations are defined with the keyword `impl`.
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type Circle = {radius: float, center: Point};
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impl Circle: Shape {
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impl Shape for Circle {
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fn draw(s: Surface) { do_draw_circle(s, self); }
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fn bounding_box() -> BoundingBox {
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let r = self.radius;
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@ -1303,9 +1303,9 @@ impl Circle: Shape {
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~~~~
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It is possible to define an implementation without referring to a trait.
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The methods in such an implementation can only be used statically
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(as direct calls on the values of the type that the implementation targets).
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In such an implementation, the type after the colon is omitted.
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The methods in such an implementation can only be used
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as direct calls on the values of the type that the implementation targets.
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In such an implementation, the trait type and `for` after `impl` are omitted.
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Such implementations are limited to nominal types (enums, structs),
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and the implementation must appear in the same module or a sub-module as the `self` type.
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@ -1320,10 +1320,10 @@ Implementation parameters are written after after the `impl` keyword.
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~~~~
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# trait Seq<T> { }
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impl<T> ~[T]: Seq<T> {
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impl<T> Seq<T> for ~[T] {
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...
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}
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impl u32: Seq<bool> {
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impl Seq<bool> for u32 {
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/* Treat the integer as a sequence of bits */
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}
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~~~~
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@ -2801,7 +2801,7 @@ trait Printable {
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fn to_str() -> ~str;
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}
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impl int: Printable {
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impl Printable for int {
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fn to_str() -> ~str { int::to_str(self) }
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}
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@ -2844,7 +2844,7 @@ trait Printable {
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fn make_string() -> ~str;
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}
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impl ~str: Printable {
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impl Printable for ~str {
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fn make_string() -> ~str { copy self }
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}
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~~~~~~~~
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@ -1909,7 +1909,7 @@ struct TimeBomb {
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explosivity: uint
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}
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impl TimeBomb : Drop {
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impl Drop for TimeBomb {
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fn finalize(&self) {
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for iter::repeat(self.explosivity) {
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io::println("blam!");
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@ -1943,11 +1943,11 @@ and `&str`.
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~~~~
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# trait Printable { fn print(&self); }
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impl int: Printable {
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impl Printable for int {
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fn print(&self) { io::println(fmt!("%d", *self)) }
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}
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impl &str: Printable {
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impl Printable for &str {
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fn print(&self) { io::println(*self) }
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}
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@ -1966,7 +1966,7 @@ trait Seq<T> {
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fn iter(&self, b: fn(v: &T));
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}
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impl<T> ~[T]: Seq<T> {
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impl<T> Seq<T> for ~[T] {
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fn len(&self) -> uint { vec::len(*self) }
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fn iter(&self, b: fn(v: &T)) {
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for vec::each(*self) |elt| { b(elt); }
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@ -1978,7 +1978,7 @@ The implementation has to explicitly declare the type parameter that
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it binds, `T`, before using it to specify its trait type. Rust
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requires this declaration because the `impl` could also, for example,
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specify an implementation of `Seq<int>`. The trait type (appearing
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after the colon in the `impl`) *refers* to a type, rather than
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between `impl` and `for`) *refers* to a type, rather than
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defining one.
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The type parameters bound by a trait are in scope in each of the
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@ -2000,7 +2000,7 @@ trait Eq {
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}
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// In an impl, `self` refers just to the value of the receiver
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impl int: Eq {
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impl Eq for int {
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fn equals(&self, other: &int) -> bool { *other == *self }
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}
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~~~~
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@ -2021,10 +2021,10 @@ trait Shape { static fn new(area: float) -> Self; }
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struct Circle { radius: float }
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struct Square { length: float }
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impl Circle: Shape {
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impl Shape for Circle {
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static fn new(area: float) -> Circle { Circle { radius: sqrt(area / pi) } }
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}
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impl Square: Shape {
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impl Shape for Square {
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static fn new(area: float) -> Square { Square { length: sqrt(area) } }
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}
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@ -2084,7 +2084,7 @@ However, consider this function:
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~~~~
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# type Circle = int; type Rectangle = int;
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# impl int: Drawable { fn draw(&self) {} }
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# impl Drawable for int { fn draw(&self) {} }
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# fn new_circle() -> int { 1 }
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trait Drawable { fn draw(&self); }
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@ -2120,9 +2120,8 @@ value to an object:
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# fn new_rectangle() -> Rectangle { true }
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# fn draw_all(shapes: &[@Drawable]) {}
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impl Circle: Drawable { fn draw(&self) { ... } }
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impl Rectangle: Drawable { fn draw(&self) { ... } }
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impl Drawable for Circle { fn draw(&self) { ... } }
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impl Drawable for Rectangle { fn draw(&self) { ... } }
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let c: @Circle = @new_circle();
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let r: @Rectangle = @new_rectangle();
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@ -2140,7 +2139,7 @@ for example, an `@Circle` may not be cast to an `~Drawable`.
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~~~
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# type Circle = int; type Rectangle = int;
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# trait Drawable { fn draw(&self); }
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# impl int: Drawable { fn draw(&self) {} }
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# impl Drawable for int { fn draw(&self) {} }
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# fn new_circle() -> int { 1 }
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# fn new_rectangle() -> int { 2 }
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// A managed object
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@ -2180,10 +2179,10 @@ Now, we can implement `Circle` on a type only if we also implement `Shape`.
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# use float::sqrt;
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# fn square(x: float) -> float { x * x }
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struct CircleStruct { center: Point, radius: float }
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impl CircleStruct: Circle {
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impl Circle for CircleStruct {
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fn radius(&self) -> float { sqrt(self.area() / pi) }
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}
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impl CircleStruct: Shape {
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impl Shape for CircleStruct {
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fn area(&self) -> float { pi * square(self.radius) }
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}
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~~~~
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@ -2215,8 +2214,8 @@ Likewise, supertrait methods may also be called on trait objects.
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# use float::sqrt;
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# struct Point { x: float, y: float }
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# struct CircleStruct { center: Point, radius: float }
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# impl CircleStruct: Circle { fn radius(&self) -> float { sqrt(self.area() / pi) } }
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# impl CircleStruct: Shape { fn area(&self) -> float { pi * square(self.radius) } }
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# impl Circle for CircleStruct { fn radius(&self) -> float { sqrt(self.area() / pi) } }
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# impl Shape for CircleStruct { fn area(&self) -> float { pi * square(self.radius) } }
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let concrete = @CircleStruct{center:Point{x:3f,y:4f},radius:5f};
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let mycircle: Circle = concrete as @Circle;
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