Cargo Features

regress = { version = "0.9.0", default-features = false, features = ["std", "backend-pikevm", "index-positions", "prohibit-unsafe", "utf16"] }
default = backend-pikevm, std

These default features are set whenever regress is added without default-features = false somewhere in the dependency tree.

std default

Enables std of memchr


The 'std' feature permits the memchr crate to use the standard library. This permits this crate to use runtime CPU feature detection to automatically accelerate searching via vector instructions. Without the standard library,
this automatic detection is not possible.

backend-pikevm default

Enables the PikeVM backend.

Affects api::backends.PikeVMExecutor


Prefers indexes to pointers for bytecode IP and string positions, for the paranoid.

Affects position::DefPosition


Prohibits all uses of unsafe code, for the paranoid.


Enables UTF-16 support. This disables some optimizations, so it should only be used when necessary.

Affects indexing::Utf16Input, indexing::Ucs2Input, matchers::Utf16CharProperties