Terry J. Reedy added the comment: Guido, do you think PEP 8 should say anything about Comment-out Blocks? It would not hurt, but one could say that since they are part of code development, and not usually a permanent part of committed code, they are out of scope, like choice of editor. On the other hand, if they are left in stdlib code, I think that they should at least be distinct from text comments. I presume that whoever added this feature to IDLE followed pre-existing practice. Anthropolist: The comment-out feature predates my involvement with IDLE, but it is a useful feature for code maintenance. Comment-out blocks are not inline comments. They are more like comment blocks, which PEP 8 discusses just above inline comments. However, the context natural language, default English, comments, so the guidelines do not apply. Disabled code blocks have a different purpose and lifetime and in my opinion should be visually distinct. If one manually comments out code with single hashes on the left margin, like so: #def f(): # def b(): # nonlocal c Uncomment Region will remove them. If comment-out hashes are indented, like so ##def f(): ## def b(): ## nonlocal c one can dedent and then uncomment. Indeed, one can dedent, comment-out, and indent to add such to code. --- I recursively grepped 3.9 /Lib for lines containing '##' and got 1596. Some are header or separator lines. Some are emphasized text comment blocks (sometimes with '###'). Some xml and xmlrpc files have a convention of prefixing comment blocks with a line containing only '##'. There are at least a few hundred commented-out code lines, perhaps half in idlelib, and mostly in tests. Sometimes '##' is followed by a space, even within idlelib. Sometimes '##' is indented instead of flush left. I suspect that these differences are editor related. An editor aimed at experts, which is not IDLE, might have comment-out and uncomment options to adjust the number of #s, a following space or not, and an indent or not. ---------- nosy: +gvanrossum _______________________________________ Python tracker https://bugs.python.org/issue41184 _______________________________________