Type Alias CowHashMap 

pub type CowHashMap<K, V> = HashMap<K, V>;

Copy-on-write associative store used for subshell snapshot/restore.

Currently a transparent alias over the standard HashMap so the SubshellSnapshot clone-in / assign-out call sites typecheck. The name is stable so the backing type can become a genuine structural CoW map (Arc-shared until first mutation) without a call-site churn.

Aliased Type

pub struct CowHashMap<K, V> { /* private fields */ }