Struct NullTracker 

pub struct NullTracker {
    pub status: HashMap<String, Nullability>,
    pub alarms: Vec<String>,
}

Tracks nullability for program variables.

Fields

status: HashMap<String, Nullability>

Nullability status per variable.

alarms: Vec<String>

Variables that caused a null dereference alarm.

Implementations

impl NullTracker

pub fn new() -> Self

Create a new null tracker.

pub fn declare_non_null(&mut self, var: impl Into<String>)

Declare a variable as definitely non-null (e.g. just allocated).

pub fn declare_maybe_null(&mut self, var: impl Into<String>)

Declare a variable as potentially null (e.g. result of nullable function).

pub fn declare_null(&mut self, var: impl Into<String>)

Declare a variable as definitely null.

pub fn get(&self, var: &str) -> &Nullability

Get the nullability of a variable (defaults to MaybeNull if unknown).

pub fn dereference(&mut self, var: &str)

Simulate a dereference: raises an alarm if var may be null.

pub fn join(&self, other: &NullTracker) -> NullTracker

Join two null-tracker states at a merge point.

pub fn has_alarm(&self) -> bool

Returns true if any null-dereference alarm was raised.

Trait Implementations

impl Clone for NullTracker

fn clone(&self) -> NullTracker

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for NullTracker

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for NullTracker

fn default() -> NullTracker

Returns the “default value” for a type.