Struct calc::Context

pub struct Context<N> {
    pub history: Vec<N>,
}

Calculation context.

Stores a history of calculated values, so that the history lookups (@) work properly. Also reifies the numeric type backing the calculations.

Fields

history: Vec<N>

Implementations

impl<N> Context<N> where
    N: Debug + Calcable,
    <N as Calcable>::Err: 'static, 

pub fn evaluate(&mut self, expr: &str) -> Result<N, Error<N>>

Evaluate an expression in this context.

This both returns the calculated value and stores a copy in the context’s history.

impl<N> Context<N> where
    N: Debug + Calcable + Numeric,
    <N as Calcable>::Err: 'static, 

pub fn evaluate_annotated(&mut self, expr: &str) -> Result<String, Error<N>>

Evaluate an annotated expression in this context.

Annotations can include output formatting directives. Therefore, the return value is a formatted String.

This also stores a copy in the context’s history.

Trait Implementations

impl<N: Default> Default for Context<N>

fn default() -> Context<N>

Returns the “default value” for a type.