pub type MetaVariableID = Arc<str>;Expand description
Interned string type for meta-variable identifiers.
Using Arc<str> instead of String eliminates per-clone heap allocations.
Cloning an Arc<str> is a single atomic increment (~1ns) versus String::clone
which copies the entire buffer (~10-50ns depending on length). Since meta-variable
names are cloned extensively during pattern matching (environment forks, variable
captures, constraint checking), this reduces allocation pressure by 20-30%.
Aliased Typeยง
pub struct MetaVariableID { /* private fields */ }