Add Display subtype for multimedia display about imageview.jl

[timholy]

Closed via 8647951

[timholy]

Hmm. Not sure I like this. Since ImageView can display both matrices and image types, now

A = rand(3,5)

opens a Tk window and displays the matrix as an image (without generating any REPL output).

[stevengj]

Your display can also print it if you want.

[timholy]

In this case I think I want the "less rich" representation by default, and get the "more rich" representation when I ask for it. Possible?

[timholy]

(The reason being that so many command-line operations generate arrays that have nothing to do with images, so opening up an image viewer for each returned array seems pointless.)

[stevengj]

In that case, just don't push the display by default. If someone wants the imageviewer, they can type display(ImageViewer, x) explicitly (or you can define some synonym, e.g. show).

Or define your display function only for Image types, and write a separate show(A) function (or plot or whatever) for matrices

[timholy]

Well, show is already defined for matrices, and I think that's best left for text-level output.

Alright, I'll figure something out. I'll probably switch to view (which makes a certain amount of sense given the name of the package) and go back to just not integrating withDisplay. This is the kind of thing that I was concerned about when you initially proposed using the name display, but I didn't foresee this precise problem.

This doesn't affect writemime for images, which is already defined and allows seamless display of images in IJulia.