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37 lines
884 B
Markdown
37 lines
884 B
Markdown
# Constructors
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## Description
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Rust does not have constructors as a language construct. Instead, the
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convention is to use a static `new` method to create an object.
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## Example
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```rust,ignore
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// A Rust vector, see liballoc/vec.rs
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pub struct Vec<T> {
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buf: RawVec<T>,
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len: usize,
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}
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impl<T> Vec<T> {
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// Constructs a new, empty `Vec<T>`.
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// Note this is a static method - no self.
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// This constructor doesn't take any arguments, but some might in order to
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// properly initialise an object
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pub fn new() -> Vec<T> {
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// Create a new Vec with fields properly initialised.
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Vec {
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// Note that here we are calling RawVec's constructor.
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buf: RawVec::new(),
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len: 0,
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}
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}
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}
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```
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## See also
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The [builder pattern](../patterns/builder.md) for constructing objects where
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there are multiple configurations.
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