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3be2b2aaa5
I missed a ["__0"] to access the str in the Static case. Also, simplify the code to rely on the pretty printer for str rather than accessing data_ptr/length directly. This makes it more robust against changes in str. Output before: "<SmolStr Static error: There is no member named data_ptr.>" Output after: "preferred-width"
smol_str
A SmolStr is a string type that has the following properties:
size_of::<SmolStr>() == 24(therefore== size_of::<String>()on 64 bit platforms)CloneisO(1)- Strings are stack-allocated if they are:
- Up to 23 bytes long
- Longer than 23 bytes, but substrings of
WS(seesrc/lib.rs). Such strings consist solely of consecutive newlines, followed by consecutive spaces
- If a string does not satisfy the aforementioned conditions, it is heap-allocated
- Additionally, a
SmolStrcan be explicitly created from a&'static strwithout allocation
Unlike String, however, SmolStr is immutable. The primary use case for
SmolStr is a good enough default storage for tokens of typical programming
languages. Strings consisting of a series of newlines, followed by a series of
whitespace are a typical pattern in computer programs because of indentation.
Note that a specialized interner might be a better solution for some use cases.
Benchmarks
Run criterion benches with
cargo bench --bench \* -- --quick
MSRV Policy
Minimal Supported Rust Version: latest stable.
Bumping MSRV is not considered a semver-breaking change.