Struct Context 

pub struct Context {
    pub vars: HashMap<String, Value>,
    pub now_serial: Option<f64>,
}

Holds the named variable bindings for a formula evaluation.

All keys are stored and looked up in uppercase, so variable names are case-insensitive (A1, a1, and A1 all refer to the same binding).

Fields

vars: HashMap<String, Value>

now_serial: Option<f64>

Pinned “now” for volatile date functions (NOW, TODAY), as a local-time spreadsheet serial datetime (integer part = day serial, fraction = time of day). None ⇒ the functions read the ambient local clock. Set via crate::Engine::evaluate_at (P1.4, issue #526).

Implementations

impl Context

pub fn new(vars: HashMap<String, Value>) -> Self

Create a Context from a map of variable name → value. Keys are normalised to uppercase on insertion.

pub fn empty() -> Self

Create an empty Context with no variable bindings.

pub fn get(&self, name: &str) -> Value

Look up a variable by name (case-insensitive). Returns Value::Empty if not found.

pub fn lookup(&self, name: &str) -> Option<Value>

Look up a binding by name (case-insensitive), distinguishing an absent binding (None) from one explicitly bound to Value::Empty (Some(Value::Empty)). Used by the evaluator to decide whether a reference should fall through to the resolver.

pub fn set(&mut self, name: String, value: Value) -> Option<Value>

Insert or overwrite a binding. Returns the previous value if one existed.

pub fn remove(&mut self, name: &str)

Remove a binding. Used to restore context after lambda/let evaluation.