Struct PredicateCompiler 

pub struct PredicateCompiler { /* private fields */ }

Compiles query predicates into executable FHE circuits

The PredicateCompiler transforms high-level query predicates (like age > 18) into FHE circuits that can evaluate these conditions on encrypted data. The result is always an encrypted boolean indicating whether the predicate matches or not.

Example

use amaters_core::compute::{PredicateCompiler, EncryptedType};
use amaters_core::types::{Predicate, col, CipherBlob};

let mut compiler = PredicateCompiler::new();

// Compile: age > 18
let predicate = Predicate::Gt(col("age"), encrypted_18);
let circuit = compiler.compile(&predicate, EncryptedType::U8)?;

// The circuit can now be executed on encrypted age values

Implementations

impl PredicateCompiler

pub fn new() -> Self

Create a new predicate compiler

pub fn compile( &mut self, predicate: &Predicate, value_type: EncryptedType, ) -> Result<Circuit>

Compile a predicate into an FHE circuit

The resulting circuit will have inputs for:

• value: The encrypted column value to test
• rhs: The encrypted comparison value (right-hand side)

The circuit output is an encrypted boolean indicating the predicate result.

Arguments

• predicate - The predicate to compile
• value_type - The encrypted type of the values being compared

Returns

A Circuit that evaluates the predicate on encrypted data

Errors

Returns an error if:

• The predicate references undefined columns
• Type inference fails
• The circuit construction is invalid

pub fn extract_rhs_value(predicate: &Predicate) -> Result<CipherBlob>

Extract the RHS (right-hand side) value from a predicate

This walks the predicate tree to find comparison values. For composite predicates (And/Or/Not), it extracts from the first comparison it encounters.

Arguments

• predicate - The predicate to extract from

Returns

The encrypted value used in the predicate comparison

Errors

Returns an error if the predicate contains no comparison operations

pub fn extract_all_rhs_values(predicate: &Predicate) -> Vec<CipherBlob>

Extract all RHS values from a predicate

For composite predicates, this returns all comparison values. This is useful for complex predicates like age > 18 AND age < 65 which have multiple RHS values.

Arguments

• predicate - The predicate to extract from

Returns

A vector of all encrypted values used in comparisons

pub fn infer_value_type(_predicate: &Predicate) -> Option<EncryptedType>

Get the required encrypted type for a predicate’s values

This analyzes the predicate to determine what type of encrypted values it operates on. This is useful for automatic type inference.

Arguments

• predicate - The predicate to analyze

Returns

The encrypted type hint, or None if it cannot be determined

Trait Implementations

impl Default for PredicateCompiler

fn default() -> Self

Returns the “default value” for a type.