Struct ReducerPlan 

pub struct ReducerPlan { /* private fields */ }

Reducers bound to the columns of one stat layout, in output order.

Implementations

impl ReducerPlan

pub fn bind( columns: &StatColumns, specs: &[ReducerSpec], defaults: bool, ) -> Result<Self, ReducerError>

Binds the default reducers when defaults is set, then each of specs, to columns of columns.

The defaults come column by column. A reducer already bound, by default or by an earlier spec, is not bound again.

Errors

Returns ReducerError::UnknownColumn for a spec whose column StatColumns::resolve cannot find.

pub fn len(&self) -> usize

Number of reducers.

pub fn is_empty(&self) -> bool

Returns whether the plan binds no reducer.

pub fn names(&self) -> &[String]

Output column names, before CSV escaping.

pub fn column(&self, i: usize) -> usize

Returns the stat column that reducer i reads.

Panics

Panics when i is not below Self::len.

pub fn kind(&self, i: usize) -> ReducerKind

Returns the fold that reducer i applies.

Panics

Panics when i is not below Self::len.

Trait Implementations

impl Clone for ReducerPlan

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ReducerPlan

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

Formats the value using the given formatter.

impl Default for ReducerPlan

fn default() -> Self

Returns the “default value” for a type.

impl PartialEq for ReducerPlan

fn eq(&self, other: &Self) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for ReducerPlan