Const generics
Const generics are generic parameters whose values are compile-time constants rather than types or runtime values.
Learn Rust in a Month of Lunches
Const generics are Rust generics that parameterize types or implementations with compile-time constant values.
- How it is used
- Uses compile-time values to make array-oriented structs and implementations reusable across lengths.
- How deep it goes
- Defines const parameters and works through array buffers, but stops short of compiler internals or advanced constraints.
- Examples
- Demonstrates fixed-size byte buffers, reusable Buffers<T, const N> structs, and concrete arrays with different types and lengths.
- What you can do after
- Build reusable array-backed structs whose element types and lengths are selected at compile time.
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Idiomatic Rust
A const generic is a Rust generic parameter whose value is a compile-time constant rather than a type.
- How it is used
- Uses compile-time values as generic parameters to make fixed-size structures, such as arrays, work with arbitrary lengths.
- How deep it goes
- Defines the syntax, permitted parameter types, and generic array conversion, but does not detail compiler internals.
- Examples
- Demonstrates a generic Buffer, conversion from arrays, and debug output for a four-element buffer.
- What you can do after
- Build it from scratch by defining a Buffer with a const length parameter and implementing conversion from arrays.
Related concepts
- arrayaddresses · An array is an indexed, ordered collection of elements arranged in one or more dimensions, with elements accessed by position.
- macroaddressed by · A macro is a named construct that expands or transforms source code, commands, or templates before or during execution.
- pointer-sized integeruses · A pointer-sized integer is a signed or unsigned integer type whose width matches the target platform’s pointer size.
- genericskind of · Generics are programming-language constructs that parameterize or generalize types and operations so they can apply to multiple concrete types or input forms.
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