using ModelingToolkit
@time @eval @mtkmodel Mod begin
end;
# this PR
# 0.851972 seconds (3.93 M allocations: 202.397 MiB, 4.32% gc time, 99.68% compilation time: 88% of which was recompilation)
# master
# 16.592960 seconds (114.90 M allocations: 5.945 GiB, 9.04% gc time, 99.97% compilation time)

using ModelingToolkit
@time @eval @mtkmodel Mod begin
    @variables begin
        x(t)
        y(t)
    end
    @parameters begin
        p
    end
    @equations begin
        x ~ y + p
    end
end;
# this PR
# 3.384142 seconds (5.87 M allocations: 305.992 MiB, 1.34% gc time, 99.75% compilation time: 41% of which was recompilation)
# master
# 22.175370 seconds (121.23 M allocations: 6.330 GiB, 5.06% gc time, 99.96% compilation time: <1% of which was recompilation)

@time using ModelingToolkit
@time @eval @mtkmodel Mod begin
    @constants begin
        c = 1.0
    end
    @structural_parameters begin
        structp = false
    end
    @variables begin
        x(t) = 0.0, [description="foo", guess=1.0]
    end
    @parameters begin
        a = 1.0, [description="bar"]
        if structp
            b=2*a, [description="if"]
        else
            c
        end
    end
    @equations begin
        x ~ a + b
    end
end;
# this PR
# 4.351150 seconds (7.32 M allocations: 378.812 MiB, 1.70% gc time, 99.69% compilation time: 47% of which was recompilation)
# master
# 24.336051 seconds (125.52 M allocations: 6.563 GiB, 6.53% gc time, 99.95% compilation time: <1% of which was recompilation)