Modify Formulation and its behavior.

src/Essentials/Frameworks.jl

@@ -170,31 +170,20 @@ Expand the generator, that is, get the (representations of the) quantum operator
 @inline expand!(result, gen::AbstractGenerator) = error("expand! error: not implemented for $(nameof(typeof(gen))).")
 
 """
-    Formulation{F<:Function, P<:Parameters, A<:NamedTuple, K<:NamedTuple, V} <: AbstractGenerator
+    Formulation{F<:Function, P<:Parameters} <: AbstractGenerator
 
 Generator of (representations of the) quantum operators of a quantum lattice system by analytical expressions.
 """
-mutable struct Formulation{F<:Function, P<:Parameters, A<:NamedTuple, K<:NamedTuple, V} <: AbstractGenerator
+mutable struct Formulation{F<:Function, P<:Parameters} <: AbstractGenerator
     formula::F
     parameters::P
-    args::A
-    kwargs::K
-    function Formulation(formula::Function, parameters::Parameters, args::NamedTuple; kwargs...)
-        kwargs = NamedTuple(kwargs)
-        V = commontype(formula, (fieldtypes(typeof(parameters))..., fieldtypes(typeof(args))...))
-        new{typeof(formula), typeof(parameters), typeof(args), typeof(kwargs), V}(formula, parameters, args, kwargs)
-    end
 end
-@inline Base.eltype(F::Type{<:Formulation}) = valtype(F)
-@inline Base.valtype(::Type{<:Formulation{<:Function, <:Parameters, <:NamedTuple, <:NamedTuple, V}}) where V = V
-@inline expand(formulation::Formulation) = formulation.formula(values(formulation.parameters)..., formulation.args...; formulation.kwargs...)
-@inline function update!(formulation::Formulation; kwargs...)
-    formulation.parameters = update(formulation.parameters; kwargs...)
-    formulation.args = update(formulation.args; kwargs...)
-    formulation.kwargs = update(formulation.kwargs; kwargs...)
+@inline function update!(formulation::Formulation; parameters...)
+    formulation.parameters = update(formulation.parameters; parameters...)
     return formulation
 end
 @inline Parameters(formulation::Formulation) = formulation.parameters
+@inline (formulation::Formulation)(; kwargs...) = formulation.formula(values(formulation.parameters)...; kwargs...)
 
 """
     Entry{C, A<:NamedTuple, B<:NamedTuple, P<:Parameters, D<:Boundary} <: AbstractGenerator

test/Essentials/Frameworks.jl

@@ -91,17 +91,16 @@ end
 end
 
 @testset "Formulation" begin
-    A(t, μ, Δ, k) = [
+    A(t, μ, Δ; k) = [
           2t*cos(k[1])+2t*cos(k[2])+μ   2im*Δ*sin(k[1])+2Δ*sin(k[2]);
         -2im*Δ*sin(k[1])+2Δ*sin(k[2])   -2t*cos(k[1])-2t*cos(k[2])-μ
     ]
-    f = Formulation(A, (t=1.0, μ=0.0, Δ=0.1), (k=[0.0, 0.0],))
-    @test valtype(f) == valtype(typeof(f)) == eltype(f) == eltype(typeof(f)) == Matrix{ComplexF64}
+    f = Formulation(A, (t=1.0, μ=0.0, Δ=0.1))
     @test Parameters(f) == (t=1.0, μ=0.0, Δ=0.1)
-    @test expand(f) ≈ [4 0; 0 -4]
+    @test f(k=[0.0, 0.0]) ≈ [4 0; 0 -4]
 
-    update!(f; μ=0.3, k=[pi/2, pi/2])
-    @test expand(f) ≈ [0.3 0.2+0.2im; 0.2-0.2im -0.3]
+    update!(f; μ=0.3)
+    @test f(k=[pi/2, pi/2]) ≈ [0.3 0.2+0.2im; 0.2-0.2im -0.3]
 end
 
 @testset "Generator" begin