There was eleven of us last night, so this is just the bits of conversation I heard.
strace(1) is handy for looking at the system calls a program makes to the kernel, try `groups' and then `sudo -i strace -tte file groups'. Facebook's React has spread to Android and iOS. "React Native lets you build mobile apps using only JavaScript. It uses the same design as React, letting you compose a rich mobile UI from declarative components." — https://facebook.github.io/react-native/ Python has descriptor classes; those with __get__(), __set__(), and others. These functions get called when an instance of the class is in another object's class dictionary. https://docs.python.org/3/reference/datamodel.html#implementing-descriptors >>> class Desc(): ... def __get__(*a): ... print('get:', *a) ... >>> class Foo(): ... a = Desc() ... >>> f = Foo() >>> f.a get: <__main__.Desc object at 0x7f4426523240> <__main__.Foo object at 0x7f4426523278> <class '__main__.Foo'> >>> As well as duck typing, there's a convention in Python called, by some, goose typing. Built-ins isinstance() and issubclass() bow to a `check' function, if it's defined, and that can use reflection to do the test. https://docs.python.org/3/library/collections.abc.html https://www.python.org/dev/peps/pep-3119/ >>> from collections import abc >>> class Iter: ... def __iter__(my): ... raise StopIteration ... >>> issubclass(Iter, abc.Iterable) True >>> isinstance(Iter(), abc.Iterable) True >>> abc.Iterable.__instancecheck__ <bound method ABCMeta.__instancecheck__ of <class 'collections.abc.Iterable'>> >>> abc.Iterable.__instancecheck__(Iter()) True >>> abc.Iterable.__instancecheck__(list()) True >>> abc.Iterable.__instancecheck__(dict()) True >>> abc.Iterable.__instancecheck__(set()) True >>> abc.Iterable.__instancecheck__(open('/dev/null')) True >>> abc.Iterable.__instancecheck__(lambda: None) False "Cython is an optimising static compiler for both the Python programming language and the extended Cython programming language... The Cython language is a superset of the Python language that additionally supports calling C functions and declaring C types on variables and class attributes. This allows the compiler to generate very efficient C code from Cython code. The C code is generated once" — http://cython.org/ "Coconut is a functional programming language that compiles to Python [2 or 3]. Since all valid Python is valid Coconut, using Coconut will only extend and enhance what you're already capable of in Python... range(10) |> map$(pow$(?, 2)) |> list" — http://coconut-lang.org/ Undebt is Python that uses the handy PyParsing library to re-factor a tree of source code, mapping an old fragment of grammar to new, e.g. `x = x + 1' to `x += 1' regardless of the complexity of the expression `x'. It can be used for any language, but comes with Python-grammar definitions. A project could build up a set of transformations over time that are repeatedly run to keep converting to the house style. https://engineeringblog.yelp.com/2016/08/undebt-how-we-refactored-3-million-lines-of-code.html gpg(1)'s -c is good for encrypting single files, rather than one of the "zip" formats. By default, it compresses the plaintext before encrypting. $ dd if=/dev/zero bs=1k count=1k of=zeroes 1024+0 records in 1024+0 records out 1048576 bytes (1.0 MB, 1.0 MiB) copied, 0.012425 s, 84.4 MB/s $ gpg -c zeroes $ du * 1024 zeroes 4 zeroes.gpg $ "memfd_create() creates an anonymous file and returns a file descriptor that refers to it. The file behaves like a regular file, and so can be modified, truncated, memory-mapped, and so on. However, unlike a regular file, it lives in RAM and has a volatile backing storage. ...a simple alternative to manually mounting a tmpfs(5) filesystem and creating and opening a file... ...primary purpose... used with the file-sealing APIs provided by fcntl(2)." — memfd_create(2) Using a fractional number of bits per input symbol. "arithmetic coding encodes the entire message into a single number, an arbitrary-precision fraction q where 0 ≤ q < 1" — https://en.wikipedia.org/wiki/Arithmetic_coding Persecution of a minority. gauche Unsophisticated and socially awkward. Mid 18th century: French, literally ‘left’. — https://en.oxforddictionaries.com/definition/gauche dexterous Early 17th century (in the sense ‘mentally adroit’): from Latin dexter ‘on the right’ + -ous. — https://en.oxforddictionaries.com/definition/dexterous sinister Late Middle English (in the sense ‘malicious, underhand’): from Old French sinistre or Latin sinister ‘left’. — https://en.oxforddictionaries.com/definition/sinister cack handed derogatory Left-handed. Mid 19th century: from cack, in the sense ‘excrement’, + hand + -ed. — https://en.oxforddictionaries.com/definition/cack-handed Patterns on Rubik's cube. http://www.cflmath.com/Rubik/patterns.html The Superflip. U R2 F B R B2 R U2 L B2 R U' D' R2 F R' L B2 U2 F2 https://ruwix.com/the-rubiks-cube/rubiks-cube-patterns-algorithms/ Cheers, Ralph. -- Next meeting: Bournemouth, Tuesday, 2017-09-05 20:00 Meets, Mailing list, IRC, LinkedIn, ... http://dorset.lug.org.uk/ New thread: mailto:[email protected] / CHECK IF YOU'RE REPLYING Reporting bugs well: http://goo.gl/4Xue / TO THE LIST OR THE AUTHOR
