Function value_structural_hash_key 

pub fn value_structural_hash_key(v: &VmValue) -> String

Canonical string form used as the keying material for hash_value. Different types never collide (the type name is prepended) and collection order is preserved so structurally-equal values always produce the same key. Not intended for cross-process stability; depends on the in-process iteration order for collections (Dict uses BTreeMap so keys are sorted).