Based on the conversations stemming from my previous post, it is clear that the topic was too implementation-specific. It is not clear whether dunder methods are an appropriate component of the solution (they might or might not be). This suggestion is to try to solve 2 inter-related but different issues, possibly through the same mechanism, 2 unrelated mechanisms, or partially overlapping mechanisms. Although the current `__str__` and `__repr__` concepts seem perfectly appropriate to me, I think there also is justification for a means of having standard pretty-informal (str-like) and pretty-formal (repr-like) representations for various types of object. In the informal case, it should be possible to pass information about a file object that it will be written to (especially encoding & possibly isatty()) to the representation code, and in the formal case, either the representation code should interact with the pretty-printer or it should be able to return data in a from that tells the pretty printer how to nest portions of the representation. It presumably makes sense to start by looking at prior art rather than inventing from scratch. Quotes from previous thread regarding prior art to look at: Jonathan Fine wrote: <snip>

Here's some comments on the state of the art. In addition to https://docs.python.org/3/library/pprint.html there's also https://docs.python.org/3/library/reprlib.html and https://docs.python.org/3/library/json.html I expect that these three modules have some overlap in purpose and design (but probably not in code). And if you're brave, there's also https://docs.python.org/3/library/pickle.html and https://github.com/psf/black Time to declare a special interest. I'm a long-time user and great fan of TeX / LaTeX. And some nice way of pretty-printing Python objects using TeX notation could be useful. And also related is Geoffrey French's Larch environment for editing Python, which has a pretty-printing component. http://www.britefury.com/larch_site/ with best wishes Jonathan

Alex Hall wrote:

Might be helpful to look at https://github.com/tommikaikkonen/prettyprinter and https://github.com/wolever/pprintpp