With the latest release (v 2.5.0) of Discourse (the software that powers these forums) there is a small but (can be) useful new feature. When you hover your mouse pointer over a code block defined with
x = x + 5;
etc. you should now see a small button appear in the top right corner of that code block like -
This button, when pressed, will automatically copy all the code in that code block to the clipboard. Means you no longer have to mess about trying to highlight long pieces of code in order to copy it.