[Tutor] list mail formatting

[Steven D'Aprano]

Alexander Etter wrote:

> Ah I know of what you mentioned. On an GNU Emacs mailing list I was advised to avoid anything but plaintext. 
> It just seems so archaic. But I'm a novice and will learn why eventually. 

There's a number of reasons. In no particular order, and in all cases "you" is 
generic you, not you personally.

* Mastery of your tools. Are you the master of your tools, or are they the 
master of you? If the writer can't turn off HTML mail in common mail clients, 
there is little hope that he can control a compiler, an editor, source 
control, etc. And if he *won't* turn it off, that shows laziness and 
carelessness to others that reflects badly. Especially in the open source 
coding community, including here, your reputation is worth more than gold.

* Code is plain text. Editors sometimes use colour and formatting to highlight 
parts of the code, but fundamentally, programming is about reading and writing 
code. If you need fancy fonts and formatting and dancing paperclips to get 
your message across, chances are you will never be more than a mediocre 
programmer.

* Mail client independence. The people you are writing to use a wide variety 
of mail clients, under many different circumstances. They might be logged into 
a Unix server with only a primitive command-line mail app; they might be using 
mutt, or Thunderbird, or Outlook, or possibly not even reading it via mail at 
all, but via a newsgroup on Usenet. All of these programs may display your 
message differently. You have no control over the presentation that the user 
will see -- best to make the fewest assumptions, namely, plain text, and not 
rely on features which may be missing.

* Your readers may be colour blind, and your red and green lines may look 
identical. Or they may be completely blind, and using a screen reader. Or they 
might prefer to disable HTML emails, and avoid all the dangers and problems 
with it (security vulnerabilities, privacy breaches, and the rest). Or they 
might be sick and tired of straining to reading crappy emails with light blue 
text on a slightly darker blue background. Either way, your formatting is 
lost. Don't expect people to turn on HTML display just for you.

* Layout of code (especially Python code) is special. Your mail client may 
mangle the layout. It is very common to see code posted where all indentation 
is lost, or even line breaks, so everything is squashed into a single line:

     def func(a, b): while b < 100: print b b += 1 print a-b

Or every line is separated by a blank line, which makes it a PITA to paste 
into the interactive interpreter. Even if the reader can fix the mangling, 
they shouldn't have to.


-- 
Steven