Module pool 

Arena-based filter pool for efficient nested filter construction.

This module provides a FilterPool that uses bump allocation to efficiently construct complex nested filter trees with minimal allocations.

When to Use

Use FilterPool when:

• Building deeply nested filter trees (depth > 3)
• Constructing many filters in a tight loop
• Performance profiling shows filter allocation as a bottleneck

For simple filters, use the regular Filter constructors directly.

Examples

Basic Usage

use prax_query::pool::FilterPool;
use prax_query::{Filter, FilterValue};

let mut pool = FilterPool::new();

// Build a complex nested filter efficiently
let filter = pool.build(|b| {
    b.and(vec![
        b.eq("status", "active"),
        b.or(vec![
            b.gt("age", 18),
            b.eq("verified", true),
        ]),
        b.not(b.eq("deleted", true)),
    ])
});

// The filter is now a regular owned Filter
assert!(!filter.is_none());

Reusing the Pool

use prax_query::pool::FilterPool;

let mut pool = FilterPool::new();

// Build first filter
let filter1 = pool.build(|b| b.eq("id", 1));

// Reset and reuse the pool
pool.reset();

// Build second filter (reuses the same memory)
let filter2 = pool.build(|b| b.eq("id", 2));

Structs

FilterBuilder

A builder for constructing filters within a pool.

FilterPool

A memory pool for efficient filter construction.

Enums

PooledFilter

A filter that lives in the pool’s arena.

PooledValue

A filter value that lives in the pool’s arena.

Traits

IntoPooledValue

Trait for types that can be converted to a pooled value.