Struct Selector 

pub struct Selector<'ctx, F> { /* private fields */ }

A tool for selecting among multiple items.

This is a generalization of using a BoolVar to select among two items, letting you use k bits to select among 2^k items.

Implementations

impl<'ctx, F: Ring> Selector<'ctx, F>

pub fn new(bits: &[BoolVar<'ctx, F>]) -> Self

Create a new selector, using a given number of in-circuit bits.

This selector will then be able to select among exactly 2^k items, where k is the number of bits passed in here.

It is more efficient to create one selector and reuse it.

The selection is made in ascending order, i.e. 0..00, 0..01, 0..10, … In other words, if you pass in, e.g. 010 to this function, you then will always get the 3rd (index 2) of 8 items.

pub fn select_constant(&self, constants: &[F]) -> Var<'ctx, F>

Select a constant value among 2^k possibilities.