Trait CustomValue 

pub trait CustomValue:
    Any
    + Send
    + Sync
    + Debug {
    // Required methods
    fn as_any(&self) -> &dyn Any;
    fn deep_clone(&self) -> Arc<dyn CustomValue>;
    fn eq_box(&self, other: &dyn CustomValue) -> bool;
}

Custom Value

Trait for any object that can be stored in enums::Value::Custom.

CustomValue extends MinArrow’s Value universe, allowing engines or analytics to handle intermediate states and custom types within the same pipeline abstraction as scalars, arrays, and tables.

You must then manage downcasting on top of the base enum match, so it it’s not the most ergonomic situation, but is available.

Typical use cases include:

• Accumulators, partial aggregates, or sketches.
• Custom algorithm outputs.
• Arbitrary user-defined types requiring unified pipeline integration.

Dynamic dispatch and downcasting are used at runtime to recover the inner type and perform type-specific logic, such as merging, reduction, or finalisation.

Implementation Notes:

• Manual implementation is not required.
• Any type that implements Debug, Clone, PartialEq, and is Send + Sync + 'static automatically satisfies CustomValue via the blanket impl.
• Any is automatically implemented by Rust for all 'static types.

Borrowing Constraints:

• Borrowed types cannot be used in Value::Custom directly, since Any requires 'static.
• To store borrowed data, first promote it to an owned type or wrap it in Arc.

Required Methods

fn as_any(&self) -> &dyn Any

Downcasts the type as Any

fn deep_clone(&self) -> Arc<dyn CustomValue>

Returns a deep clone of the object.

Additionally, the Value enum automatically derives Clone, which is a shallow Arc clone by default.

fn eq_box(&self, other: &dyn CustomValue) -> bool

Performs semantic equality on the boxed object.

This enables PartialEq to be implemented for Value, since dyn CustomValue cannot use == directly.

Implementors

impl<T> CustomValue for T

where T: Any + Send + Sync + Clone + PartialEq + Debug,

Provided extension types implement Clone, PartialEq, Debug and is Send + Sync + Any, these methods implement automatically.