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A monad is just a monoid in the category of endofunctors, what's the problem?
...of sets. You can read more about that here: en.wikipedia.org/wiki/Cartesian_product, but the basic idea is that an element of S × T is a pair (s, t), where s ∈ S and t ∈ T. So the signature of the monoidal product • : S × S -> S in this context simply means a function that takes 2 element...
Ship an application with a database
...ample below demonstrates how to use either method.
Here is a sample create_database.sql file. It is to be placed in the assets folder of the project for the internal method or copied into the "Execute SQL' of SQLite Manager to create the database for the external method. (NOTE: Notice the comment...
What is your most productive shortcut with Vim?
... a language. The initial y is a verb. The statement yy is a synonym for y_. The y is doubled up to make it easier to type, since it is such a common operation.
This can also be expressed as dd P (delete the current line and paste a copy back into place; leaving a copy in the anonymous register as ...
Possible to do a MySQL foreign key to one of two possible tables?
..., you can designate which target table is referenced.
CREATE TABLE popular_places (
user_id INT NOT NULL,
place_id INT NOT NULL,
place_type VARCHAR(10) -- either 'states' or 'countries'
-- foreign key is not possible
);
There's no way to model Polymorphic Associations using SQL constraint...
What characters can be used for up/down triangle (arrow without stem) for display in HTML?
...ler font.
More Unicode arrows are at:
http://en.wikipedia.org/wiki/Arrow_%28symbol%29#Arrows_in_Unicode
http://en.wikipedia.org/wiki/Geometric_Shapes
Lastly, these arrows are not ASCII, including ↑ and ↓: they are Unicode.
...
What are the real-world strengths and weaknesses of the many frameworks based on backbone.js? [close
...yApp.module("MyModule", function(MyModule, MyApp, Backbone, Marionette, $, _){
// your module code goes here
});
(No blog post available for this, yet)
Incremental Use
This is one of the core philosophies that I bake in to every part of Marionette that I can: no "all-or-nothing" requirement ...
Python base64 data decode
...
import base64
coded_string = '''Q5YACgA...'''
base64.b64decode(coded_string)
worked for me. At the risk of pasting an offensively-long result, I got:
>>> base64.b64decode(coded_string)
2: 'C\x96\x00\n\x00\x00\x00\x00C\x96\x00\x1b\x0...
What is a correct mime type for docx, pptx etc?
...mage/vnd.fst", "fvt": "video/vnd.fvt", "fbs": "image/vnd.fastbidsheet", "fe_launch": "application/vnd.denovo.fcselayout-link", "f4v": "video/x-f4v", "flv": "video/x-flv", "fpx": "image/vnd.fpx", "npx": "image/vnd.net-fpx", "flx": "text/vnd.fmi.flexstor", "fli": "video/x-fli", "ftc": "application/vnd...
Socket 错误返回码详解 - C/C++ - 清泛网 - 专注C/C++及内核技术
...etwork is unreachable
WSAETIMEDOUT (10060) Connection timed out
WSAHOST_NOT_FOUND (11001) Host not found
WSASYSNOTREADY (10091) Network sub-system is unavailable
WSANOTINITIALISED (10093) WSAStartup() not performed
WSANO_DATA (11004) Valid name, no data of that type
WSANO_RECOVERY (11003...
What is move semantics?
...ng
{
char* data;
public:
string(const char* p)
{
size_t size = std::strlen(p) + 1;
data = new char[size];
std::memcpy(data, p, size);
}
Since we chose to manage the memory ourselves, we need to follow the rule of three. I am going to defer writing the assi...