Why no := operator for initializing variables

Internals & Design
37

Here is an example illustrating the memory allocation:


julia> function f()
          A = zeros(10,10)
          B = ones(10,10)
          C = 2 .* ones(10,10)
          D = 3 .* ones(10,10)
          @time A .= B*C .+ D
          return nothing
       end
f (generic function with 1 method)

julia> f()
  0.000005 seconds (1 allocation: 896 bytes)

In fact it allocated 896 bytes, whereas I was expecting 8*10^2 = 800 bytes.