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@ -87,3 +87,33 @@ fn main() {
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point.y = 6; // this causes an error
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}
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```
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# Update syntax
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A `struct` can include `..` to indicate that you want to use a copy of some
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other struct for some of the values. For example:
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```rust
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struct Point3d {
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x: i32,
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y: i32,
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z: i32,
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}
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let mut point = Point3d { x: 0, y: 0, z: 0 };
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point = Point3d { y: 1, .. point };
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```
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This gives `point` a new `y`, but keeps the old `x` and `z` values. It doesn’t
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have to be the same `struct` either, you can use this syntax when making new
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ones, and it will copy the values you don’t specify:
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```rust
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# struct Point3d {
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# x: i32,
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# y: i32,
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# z: i32,
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# }
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let origin = Point3d { x: 0, y: 0, z: 0 };
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let point = Point3d { z: 1, x: 2, .. origin };
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```
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