pub struct AllFacts<T: FactTypes> {Show 18 fields
pub loan_issued_at: Vec<(T::Origin, T::Loan, T::Point)>,
pub universal_region: Vec<T::Origin>,
pub cfg_edge: Vec<(T::Point, T::Point)>,
pub loan_killed_at: Vec<(T::Loan, T::Point)>,
pub subset_base: Vec<(T::Origin, T::Origin, T::Point)>,
pub loan_invalidated_at: Vec<(T::Point, T::Loan)>,
pub var_used_at: Vec<(T::Variable, T::Point)>,
pub var_defined_at: Vec<(T::Variable, T::Point)>,
pub var_dropped_at: Vec<(T::Variable, T::Point)>,
pub use_of_var_derefs_origin: Vec<(T::Variable, T::Origin)>,
pub drop_of_var_derefs_origin: Vec<(T::Variable, T::Origin)>,
pub child_path: Vec<(T::Path, T::Path)>,
pub path_is_var: Vec<(T::Path, T::Variable)>,
pub path_assigned_at_base: Vec<(T::Path, T::Point)>,
pub path_moved_at_base: Vec<(T::Path, T::Point)>,
pub path_accessed_at_base: Vec<(T::Path, T::Point)>,
pub known_placeholder_subset: Vec<(T::Origin, T::Origin)>,
pub placeholder: Vec<(T::Origin, T::Loan)>,
}Expand description
The “facts” which are the basis of the NLL borrow analysis.
Fields§
§loan_issued_at: Vec<(T::Origin, T::Loan, T::Point)>loan_issued_at(origin, loan, point) indicates that the loan was “issued”
at the given point, creating a reference with the origin.
Effectively, origin may refer to data from loan starting at point (this is usually
the point after a borrow rvalue).
universal_region: Vec<T::Origin>universal_region(origin) – this is a “free region” within fn body
cfg_edge: Vec<(T::Point, T::Point)>cfg_edge(point1, point2) for each edge point1 -> point2 in the control flow
loan_killed_at: Vec<(T::Loan, T::Point)>loan_killed_at(loan, point) when some prefix of the path borrowed at loan
is assigned at point.
Indicates that the path borrowed by the loan has changed in some way that the loan no
longer needs to be tracked. (In particular, mutations to the path that was borrowed
no longer invalidate the loan)
subset_base: Vec<(T::Origin, T::Origin, T::Point)>subset_base(origin1, origin2, point) when we require origin1@point: origin2@point.
Indicates that origin1 <= origin2 – i.e., the set of loans in origin1 are a subset
of those in origin2.
loan_invalidated_at: Vec<(T::Point, T::Loan)>loan_invalidated_at(point, loan) indicates that the loan is invalidated by some action
taking place at point; if any origin that references this loan is live, this is an error.
var_used_at: Vec<(T::Variable, T::Point)>var_used_at(var, point) when the variable var is used for anything
but a drop at point
var_defined_at: Vec<(T::Variable, T::Point)>var_defined_at(var, point) when the variable var is overwritten at point
var_dropped_at: Vec<(T::Variable, T::Point)>var_dropped_at(var, point) when the variable var is used in a drop at point
use_of_var_derefs_origin: Vec<(T::Variable, T::Origin)>use_of_var_derefs_origin(variable, origin): References with the given
origin may be dereferenced when the variable is used.
In rustc, we generate this whenever the type of the variable includes the given origin.
drop_of_var_derefs_origin: Vec<(T::Variable, T::Origin)>drop_of_var_derefs_origin(var, origin) when the type of var includes
the origin and uses it when dropping
child_path: Vec<(T::Path, T::Path)>child_path(child, parent) when the path child is the direct child of
parent, e.g. child_path(x.y, x), but not child_path(x.y.z, x).
path_is_var: Vec<(T::Path, T::Variable)>path_is_var(path, var) the root path path starting in variable var.
path_assigned_at_base: Vec<(T::Path, T::Point)>path_assigned_at_base(path, point) when the path was initialized at point
point. This fact is only emitted for a prefix path, and not for the
implicit initialization of all of path’s children. E.g. a statement like
x.y = 3 at point would give the fact path_assigned_at_base(x.y, point) (but
neither path_assigned_at_base(x.y.z, point) nor path_assigned_at_base(x, point)).
path_moved_at_base: Vec<(T::Path, T::Point)>path_moved_at_base(path, point) when the path was moved at point. The
same logic is applied as for path_assigned_at_base above.
path_accessed_at_base: Vec<(T::Path, T::Point)>path_accessed_at_base(path, point) when the path was accessed at point
point. The same logic as for path_assigned_at_base and path_moved_at_base applies.
known_placeholder_subset: Vec<(T::Origin, T::Origin)>These reflect the 'a: 'b relations that are either declared by the user on function
declarations or which are inferred via implied bounds.
For example: fn foo<'a, 'b: 'a, 'c>(x: &'c &'a u32) would have two entries:
- one for the user-supplied subset
'b: 'a - and one for the
'a: 'cimplied bound from thexparameter, (note that the transitive relation'b: 'cis not necessarily included explicitly, but rather inferred by polonius).
placeholder: Vec<(T::Origin, T::Loan)>placeholder(origin, loan) describes a placeholder origin, with its associated
placeholder loan.