Enum NullCol 

pub enum NullCol {
    Int(NullableColumn<i64>),
    Float(NullableColumn<f64>),
    Str(NullableColumn<String>),
    Bool(NullableColumn<bool>),
}

A typed nullable column variant stored in a DataFrame column slot.

Phase 13-16 does not replace Column (which has no nulls) with NullCol everywhere – that would be a breaking change across the whole codebase. Instead, NullCol is used as the result type of operations that can introduce nulls (left_join fills, pivot_wider missing combinations, bind_rows on mismatched schemas, full_join unmatched rows).

Conversion: NullCol::from_column(col) wraps an existing Column as fully-valid nullable. NullCol::to_column(nc) unwraps if fully valid, else returns TidyError::Internal (caller must handle null columns explicitly).

Variants

Int(NullableColumn<i64>)

Float(NullableColumn<f64>)

Str(NullableColumn<String>)

Bool(NullableColumn<bool>)

Implementations

impl NullCol

pub fn len(&self) -> usize

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

pub fn type_name(&self) -> &'static str

pub fn from_column(col: &Column) -> Self

Wrap a non-nullable Column as fully valid.

pub fn to_column_strict(&self) -> Result<Column, TidyError>

Unwrap to non-nullable Column only if all rows are valid (not null). If any null exists, returns Err(TidyError::Internal).

pub fn to_column_filled(&self) -> Column

Convert to Column, filling nulls with type-appropriate zero-value. Null Int → 0, Null Float → NaN, Null Str → “”, Null Bool → false.

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

Get display string for a row (null → “null”).

pub fn null_of_type(type_name: &str, len: usize) -> Self

Create a null-fill column of given type and length.

pub fn gather(&self, indices: &[usize]) -> Self

Gather rows by index.

Trait Implementations

impl Clone for NullCol

fn clone(&self) -> NullCol

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for NullCol

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

Formats the value using the given formatter.