Using superscript ⁻¹ as a postfix operator for inv?

General Usage
12

You can actually do this with no language changes if you’re willing to write (A)⁻¹ rather than A⁻¹. Here’s an example at the REPL:

julia> begin
           struct Inverter end
           const ⁻¹ = Inverter()
           Base.:(*)(A, ::Inverter) = inv(A)
       end

julia> A = rand(3,3)
3×3 Array{Float64,2}:
 0.51549   0.0616877  0.530502
 0.783366  0.0598045  0.697045
 0.381722  0.833891   0.632847

julia> (A)⁻¹
3×3 Array{Float64,2}:
 -13.5368    10.0475    0.280811
  -5.72129    3.08199   1.4014
  15.704    -10.1216   -0.435822

julia> ((A)⁻¹)*A ≈ I(3)
true

This works because (a)b is parsed as a * b:

julia> quote (a)b end
quote
    #= REPL[7]:1 =#
    a * b
end

so we need only define an object ⁻¹ which when multiplied by A on the left produces inv(A), trivially easy with multiple dispatch.

One could do the same with ² to make an squaring operator if they were unable to stomach reading x^2 or x*x

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