InplaceOps.jl is a Julia package that provides macros that enable a simple syntax for performing in-place (i.e. overwriting) array operations using standard arithmetic operators.

InplaceOps.jl provides a macro @! which rewrites expressions of the form:

• C = A*B to mul!(C,A,B)
• C = C*B or C *= B to rmul!(C,B)
• C = A*C to lmul!(A,B)
• C = A/B to rdiv!(C,A,B)
• C = C/B or C /= B to rdiv!(C,B)
• C = A\B to ldiv!(C,A,B)
• C = A\C to ldiv!(A,B)

Functionality for broadcasting is no longer supported. Use the Base @. macro instead.

julia> using LinearAlgebra, InplaceOps

julia> T = UpperTriangular(ones(5,5))
5×5 UpperTriangular{Float64,Array{Float64,2}}:
 1.0  1.0  1.0  1.0  1.0
  ⋅   1.0  1.0  1.0  1.0
  ⋅    ⋅   1.0  1.0  1.0
  ⋅    ⋅    ⋅   1.0  1.0
  ⋅    ⋅    ⋅    ⋅   1.0

julia> x_orig = x = [1.0,2.0,3.0,4.0,5.0]
5-element Array{Float64,1}:
 1.0
 2.0
 3.0
 4.0
 5.0

julia> @! x = T \ x
5-element Array{Float64,1}:
 -1.0
 -1.0
 -1.0
 -1.0
  5.0

julia> x === x_orig
true