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% Constructors
### Define constructors as static, inherent methods. [FIXME: needs RFC]
In Rust, "constructors" are just a convention:
```rust
impl<T> Vec<T> {
pub fn new() -> Vec<T> { ... }
}
```
Constructors are static (no `self`) inherent methods for the type that they
construct. Combined with the practice of
[fully importing type names](../style/imports.md), this convention leads to
informative but concise construction:
```rust
use vec::Vec;
// construct a new vector
let mut v = Vec::new();
```
This convention also applied to conversion constructors (prefix `from` rather
than `new`).
### Provide constructors for passive `struct`s with defaults. [FIXME: needs RFC]
Given the `struct`
```rust
pub struct Config {
pub color: Color,
pub size: Size,
pub shape: Shape,
}
```
provide a constructor if there are sensible defaults:
```rust
impl Config {
pub fn new() -> Config {
Config {
color: Brown,
size: Medium,
shape: Square,
}
}
}
```
which then allows clients to concisely override using `struct` update syntax:
```rust
Config { color: Red, .. Config::new() };
```
See the [guideline for field privacy](../features/types/README.md) for
discussion on when to create such "passive" `struct`s with public
fields.
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