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

[Mark H Harris]

On 4/3/14 2:43 PM, Marko Rauhamaa wrote:

> What does computer science have to show of late? A better mutual
> exclusion algorithm? Dancing trees?

> Ok, cryptography has been pretty exciting. The back and forth between
> feasibility and unfeasibility. The ongoing cat and mouse.

    Computer science is stuck right now. This is for two reasons:

    1) marketing (capitalism)

    2) software idea patents (obviously marketing related)

    Two things need to happen to 'unstick' computer science: 1) 
intellectual property law needs an overhaul and software idea patents 
must die, and 2) computer languages (software engineering, coding) needs 
to be taught as a liberal art beginning seriously in middle school as an 
integrated discipline (for sure by high school, and as an absolute in 
colleges).

    Computer science needs to be freed of the capitalistic strangle-hold 
which some corporations leverage over it. Innovation is thwarted because 
its the wrong capitalistic thing to do. Innovation is thwarted because 
of the asinine world-wide intellectual property law malfunction; 
software idea patents must die.

    Cryptography is particularly annoying. Mathematicians and algorithm 
specialists are ham-strung because of the GCHQ in the U.K. and the NSA 
in the States. Our governments DO NOT want computer science to move 
forward with cryptography!  God help the guy (people) who finally figure 
out how to determine the nth prime, or figure out how to factor really 
HUGE prime numbers easily on a desktop computer (not likely to happen 
anytime soon, but for sure NOT going to happen with the NSA & GCHQ 
looking over everyone's shoulders.

    Well, as everyone pointed out integers are the focal point for 
crypto. But, what if the focal point should be 'decimal' (really large 
very fast decimals).  --- which are useful for constructing certain 
integers and ... dream with me here.   Whatever it will take WILL 
require a paradigm shift, and it will require that we stand up and 
defend our right to pursue the course. Everyone has a right to digital 
privacy. Computer science is the way forward.


marcus