Struct HGrid 

pub struct HGrid {
    pub meta: HDict,
    pub cols: Vec<HCol>,
    pub rows: Vec<HDict>,
}

Haystack Grid — the fundamental tabular data structure.

A grid has:

• meta: grid-level metadata (an HDict)
• cols: ordered list of columns (HCol)
• rows: ordered list of row dicts (HDict)

Fields

meta: HDict

cols: Vec<HCol>

rows: Vec<HDict>

Implementations

impl HGrid

pub fn new() -> Self

Create an empty grid.

pub fn from_parts(meta: HDict, cols: Vec<HCol>, rows: Vec<HDict>) -> Self

Create a grid from its constituent parts.

pub fn from_parts_arc( meta: HDict, cols: Vec<HCol>, rows: Vec<Arc<HDict>>, ) -> Self

Build a grid from Arc-wrapped rows, avoiding clones when possible.

Uses Arc::try_unwrap() to move the inner HDict when the reference count is 1 (which is the common case in request pipelines). Falls back to clone only for shared references.

pub fn col(&self, name: &str) -> Option<&HCol>

Look up a column by name. Returns None if not found.

pub fn is_empty(&self) -> bool

Returns true if the grid has no rows.

pub fn is_err(&self) -> bool

Returns true if this grid represents an error response.

An error grid has an err marker tag in its metadata.

pub fn len(&self) -> usize

Returns the number of rows.

pub fn row(&self, index: usize) -> Option<&HDict>

Returns a reference to the row at the given index.

pub fn iter(&self) -> impl Iterator<Item = &HDict>

Iterate over rows.

pub fn num_cols(&self) -> usize

Returns the number of columns.

pub fn col_names(&self) -> impl Iterator<Item = &str>

Returns an iterator over column names.

Trait Implementations

impl Clone for HGrid

fn clone(&self) -> HGrid

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for HGrid

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

Formats the value using the given formatter.

impl Default for HGrid

fn default() -> HGrid

Returns the “default value” for a type.

impl Display for HGrid

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

Formats the value using the given formatter.

impl PartialEq for HGrid

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl StructuralPartialEq for HGrid