SetBuilders.jl

Julia Package for Predicate and Enumerable Sets

SetBuilders provides Julia users with the power of predicate-based sets.

Many programming languages, including Julia, support a type of enumerable sets but not predicate sets in the mathematical sense. For instance, in Julia, it's possible to create a set containing integer values, such as

A = Set([1,2,3])

However, creating the following is not possible:

A = Set(x ∈ Integer | 0 < x < 4)

The SetBuilders package enables Julia users to create predicate sets, combine them using set operations like unions and intersections, and check if an object is a member of a set.

I = @setbuild(Integer)           # creates a set from Julia Integer type
A = @setbuild(x ∈  I, 0 < x < 4) # creates a set with the predicate of "0 < x < 4"
B = @setbuild(x in I, 2 < x < 6) # creates a set with the predicate of "2 < x < 6"
C = A ∩ B                        # creates an intersection with the two sets
                                 # As an alternative, "intersect(A, B)" can be used
@assert 3 ∈ C                    # => true, 3 is a member of the set C
                                 # As an alternative, "3 in C" can be used
@assert !(4 in C)                # => true, 4 is not a member of the set C

The @setbuild macro in SetBuilders creates various types of sets. In the above example, the set I is built using the Julia Integer data type. Meanwhile, the sets A and B are constructed by specifying the domain set and a predicate using a boolean expression, and the set C is created using the set intersection operator.

The package can be installed using the Julia package manager. From the Julia REPL, type ] to enter the Pkg REPL mode and run:

pkg> add SetBuilders

Alternatively, it can be installed via the Pkg API:

julia> import Pkg; Pkg.add("SetBuilders")

Once installed, the SetBuilders package can be loaded with using SetBuilders.

using SetBuilders

In addition to set creations, set operations, and membership tests shown in the above example, SetBuilders also provides features such as set event, set description, set element generation, and set sharing.

For more information on using the package, see the documentation.