If you have been using GNU/Linux or Python (even on on evil platforms like Mac and Windows), you will have a way of accessing help documentation in REPL, so does Julia too. To access help, just type ? in Julia prompt, you will be presented with something like this:


You can come out of help by pressing Backspace. Okay lets see what typeof (if you have read previous blog you may have used typeof) does. Just type typeof in help prompt and hit Enter.

help?> typeof
search: typeof typejoin TypeError


  Get the concrete type of x.


  julia> a = 1//2;

  julia> typeof(a)

  julia> M = [1 2; 3.5 4];

  julia> typeof(M)

Isn’t it useful?