Explanation of this Python language feature? [x for x in x for x in x] (to flatten a nested list)

[Mark H Harris]

On 3/29/14 1:03 AM, Chris Angelico wrote:
>
> http://forum.ecomstation.ru/
>
> Prominent discussion forum, although that strives to be at least
> partially bilingual in deference to those of us who are so backward as
> to speak only English.

    Yes. Well, as the joke goes, if you're trilingual you speak three 
languages, if you're bilingual you speak two languages, if you're 
monolingual you're an American (well, that might go for Australia too, 
maybe). When whole continents speak the same language that tends to happen.
>
> So, pre-Unicode, people didn't use any of those languages or writing
> systems with computers, is that what you're saying? That code pages
> 86x are a total myth?

    No, no, no... don't over-read my post please. Think in orders of 
magnitudes. In computer history very little is even mentioned outside 
the U.S.  This is, of course, not fair.  The folks in the U.K. played a 
huge role (the Alan Turing story, The Baby, Blakeley &c). The entire 
world used ASCII, like, forever.  Heck, its still being used!

    Code pages are not a myth,  but they were not prominent, either. And 
of course prejudice is relatively spoken; I don't want to define it.
    What I can tell you in my own experience, as an amateur radio 
operator (W0MHH, general class) who has communicated all over the earth 
(even to Soviet Russia), all my computer|radio comm was in English using 
Morse code sets, Latin characters, and ASCII.  No one ever asked me to 
comm in Russian, or French, nor Italian, nor Tswana...

> Unicode didn't even begin to exist until 1987, and the first version
> of the standard wasn't published until 1991. You're seriously saying
> that until 1991 (plus however long it took to get implementations into
> people's hands) everyone spoke English with computers?!?

    No. see above.   I'm saying that (for the most part) international 
communication has been Latin code pages and ASCII all over the earth, 
until very recently (as you point out).. By the way, in my view, 1991 is 
very recently; from a computer historical standpoint too. I mean, think 
about it, computers have only existed since late 1940s and only in their 
modern context since about 1989. I didn't really start using unicode 
until about 5 years ago; python has only really used it since python3. 
right?

>>     See this quote from the consortium FAQ:
>>
>>     >  So, for example, there is only one set of Latin characters
>>     > defined, despite the fact that the Latin script
>>     > is used for the alphabets of thousands of different languages.
>>
>> http://www.unicode.org/faq/basic_q.html#3
>
> Huh?

    The consortium designates scripts vs. languages. When folks ask them 
about how many languages they support its a difficult answer.  Do you 
mean scripts ( of which there is only one Latin script ) or are you 
referring to the *thousands* of different languages that are scripted in 
Latin characters?  Latin script is used in thousands of languages 
world-wide;  true story.  (that's what the quote is above)

> I'm not sure whether you're trolling or genuinely ignorant of all
> history and other languages.

    Neither.  I never troll, and I'm not ignorant. We are only getting 
cross-ways on this point more because of overlapping time frames I'm 
guessing, and numbers. I know that people groups and various languages 
were being used around the world in pockets for various purposes. I was 
part of the support group at IBM, for instance, that helped with the 
debugging process when we started supporting Kanji on the system36 
system38.  I know that kind of stuff was happening. But when it came to 
communicating world-wide for business (or in my case with radiography) 
it was always ASCII, Latin character sets, and in my case English Morse 
or international Morse code sets (derived from English).


> Please clarify. If you really are just
> trolling, say so, and I'll start ignoring all your posts.

No, Chris.  I never troll.  (that would make my fingers itch)

:)