fix: remove invalidating ::Any methods

Author: AayushSabharwal

src/MultivariatePolynomials.jl

@@ -58,6 +58,7 @@ Abstract type for a polynomial of coefficient type `T`, i.e. a sum of `AbstractT
 abstract type AbstractPolynomial{T} <: AbstractPolynomialLike{T} end
 
 const _APL{T} = AbstractPolynomialLike{T}
+const _Constant = Union{Number,MA.AbstractMutable,AbstractArray}
 
 include("zip.jl")
 include("lazy_iterators.jl")

src/comparison.jl

@@ -10,14 +10,8 @@ function Base.isone(p::AbstractPolynomial)
     return isone(nterms(p)) && isone(first(terms(p)))
 end
 
-# See https://github.com/blegat/MultivariatePolynomials.jl/issues/22
-# avoids the call to be transfered to left_constant_eq
-Base.:(==)(α::Nothing, x::_APL) = false
-Base.:(==)(x::_APL, α::Nothing) = false
 Base.:(==)(α::Dict, x::_APL) = false
 Base.:(==)(x::_APL, α::Dict) = false
-Base.:(==)(α::Nothing, x::RationalPoly) = false
-Base.:(==)(x::RationalPoly, α::Nothing) = false
 Base.:(==)(α::Dict, x::RationalPoly) = false
 Base.:(==)(x::RationalPoly, α::Dict) = false
 
@@ -133,16 +127,16 @@ Base.:(==)(p::RationalPoly, q::RationalPoly) = p.num * q.den == q.num * p.den
 # Solve ambiguity with (::PolyType, ::Any)
 Base.:(==)(p::_APL, q::RationalPoly) = p * q.den == q.num
 Base.:(==)(q::RationalPoly, p::_APL) = p == q
-Base.:(==)(α, q::RationalPoly) = α * q.den == q.num
-Base.:(==)(q::RationalPoly, α) = α == q
+Base.:(==)(α::_Constant, q::RationalPoly) = α * q.den == q.num
+Base.:(==)(q::RationalPoly, α::_Constant) = α == q
 function Base.isequal(p::RationalPoly, q::RationalPoly)
     return isequal(p.num * q.den, q.num * p.den)
 end
 # Solve ambiguity with (::PolyType, ::Any)
 Base.isequal(p::_APL, q::RationalPoly) = isequal(p * q.den, q.num)
 Base.isequal(q::RationalPoly, p::_APL) = isequal(p, q)
-Base.isequal(α, q::RationalPoly) = isequal(α * q.den, q.num)
-Base.isequal(q::RationalPoly, α) = isequal(α, q)
+Base.isequal(α::_Constant, q::RationalPoly) = isequal(α * q.den, q.num)
+Base.isequal(q::RationalPoly, α::_Constant) = isequal(α, q)
 
 # α could be a JuMP affine expression
 isapproxzero(α; ztol::Real = 0.0) = false

src/operators.jl

@@ -30,18 +30,20 @@ for (op, fun) in [
     (:+, :right_constant_plus),
     (:-, :right_constant_minus),
     (:*, :right_constant_mult),
-    (:(==), :right_constant_eq),
 ]
     @eval Base.$op(p::_APL, α) = $fun(p, α)
 end
+Base.:(==)(p::_APL, α::_Constant) = right_constant_eq(p, α)
+
 for (op, fun) in [
     (:+, :left_constant_plus),
     (:-, :left_constant_minus),
     (:*, :left_constant_mult),
-    (:(==), :left_constant_eq),
 ]
     @eval Base.$op(α, p::_APL) = $fun(α, p)
 end
+Base.:(==)(α::_Constant, p::_APL) = left_constant_eq(α, p)
+
 ## Fix ambiguity between above methods and methods in MA
 Base.:+(::MA.Zero, p::_APL) = MA.copy_if_mutable(p)
 Base.:+(p::_APL, ::MA.Zero) = MA.copy_if_mutable(p)