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Why unsigned integer is not available in PostgreSQL?
...l.org/docs/9.4/static/sql-createdomain.html
CREATE DOMAIN name [ AS ] data_type
[ COLLATE collation ]
[ DEFAULT expression ]
[ constraint [ ... ] ]
where constraint is:
[ CONSTRAINT constraint_name ]
{ NOT NULL | NULL | CHECK (expression) }
Domain is like a type but with an addition...
How to draw a line in android
...rself just simple and clean add the line in xml.
<View
android:layout_width="match_parent"
android:layout_height="1dp"
android:background="@android:color/black" />
The example code I provided will generate a line that fills the screen in width and has a height of one dp.
If you have ...
Is a colon `:` safe for friendly-URL use?
...oded / sub-delims / ":" / "@"
unreserved = ALPHA / DIGIT / "-" / "." / "_" / "~"
pct-encoded = "%" HEXDIG HEXDIG
sub-delims = "!" / "$" / "&" / "'" / "(" / ")"
/ "*" / "+" / "," / ";" / "="
Apart from these restrictions, the fragment part has no defined structure beyon...
How do I test for an empty JavaScript object?
...N.stringify({});
}
jQuery:
jQuery.isEmptyObject({}); // true
lodash:
_.isEmpty({}); // true
Underscore:
_.isEmpty({}); // true
Hoek
Hoek.deepEqual({}, {}); // true
ExtJS
Ext.Object.isEmpty({}); // true
AngularJS (version 1)
angular.equals({}, {}); // true
Ramda
R.isEmpty({}); //...
Custom exception type
...){
Object.setPrototypeOf(CustomError, Error);
} else {
CustomError.__proto__ = Error;
}
Alternative: use Classtrophobic framework
Explanation:
Why extending the Error class using ES6 and Babel is a problem?
Because an instance of CustomError is not anymore recognized as such.
class Cus...
Why do Java programmers like to name a variable “clazz”? [closed]
..."class" is what you want, but abbreviating or inserting junk ("a", "the", "_", etc) reduces clarity. clazz just says class. "International" English speakers (those reading both British and American English) are used to transposing 's' and 'z'.
Since Java has had disclosed source and a suitable cult...
What is setup.py?
...ts and also from [I]Python prompts.
It does the similar job of pip, easy_install etc.,
Using setup.py
Let's start with some definitions:
Package - A folder/directory that contains __init__.py file.
Module - A valid python file with .py extension.
Distribution - How one package relates to ...
How to enable cross-origin resource sharing (CORS) in the express.js framework on node.js
...});
app.configure('development', function () {
app.use(express.static(__dirname + '/public'));
app.use(express.errorHandler({ dumpExceptions: true, showStack: true }));
});
app.configure('production', function () {
app.use(express.static(__dirname + '/public'));
app.use(express.err...
Navigation in django
...f to do that, have a look at the following code:
tags.py
@register.simple_tag
def active(request, pattern):
import re
if re.search(pattern, request.path):
return 'active'
return ''
urls.py
urlpatterns += patterns('',
(r'/$', view_home_method, 'home_url_name'),
(r'/se...
Number of processors/cores in command line
...
The most simplest tool comes with glibc and is called getconf:
$ getconf _NPROCESSORS_ONLN
4
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