An object representing a result of a constant-time comparison, used in select and swap.

Supports !.

An abstract type to mark types for which select is defined. Usually these will be compound user types containing several Value fields.

Value{T}(value::T)
Value(value::T)

A wrapper for a type T that protects it from being used in non-constant-time operations.

This module defines some methods that are (most probably) constant-time. Namely, for built-in integer types (Int8...128 and UInt8...128), the following methods are defined: zero, one, ~, +, -, xor, &, |, % (with the second argument being a built-in integer type), signed, unsigned, iseven, isodd, iszero, ==. Also, >> and << are defined for the shift also being a built-in integer.

The functions that would otherwise return Bool will return Choice for Value objects.

Binary operations on one Value and one unwrapped value produce a Value.

get(array::Array{Value{V}, 1}, x::Value, default::Value{V}) where V <: Selectable

Constant-time array access.

select(choice::Bool, x, y)
select(choice::Choice, x::Value{T}, y::Value{T})

An analogue of a ternary operator or ifelse (which, at the moment, cannot have methods added to them).

If choice is true, returns x, else y. For choice being a Choice object, and x and y being Value objects, the operation is constant-time.

swap(choice::Bool, x, y)
swap(choice::Choice, x::Value{T}, y::Value{T})

If choice is true, returns (y, x), else (x, y). For choice being a Choice object, and x and y being Value objects, the operation is constant-time.

unwrap(x)
unwrap(x::Value)

If x is a Value, returns the wrapped value. Otherwise, returns x.

unwrap(x::Choice)

Returns the wrapped boolean value.

wrap(x)
wrap(x::Value)

If x is a Value, returns x, otherwise wraps x in a Value.