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Why aren't variables declared in “try” in scope in “catch” or “finally”?
...Reader sr,
[1] class [mscorlib]System.Exception ex)
IL_0000: ldnull
IL_0001: stloc.0
.try
{
.try
{
IL_0002: ldsfld string UsingTest.Class1::path
IL_0007: newobj instance void [mscorlib]System.IO.StreamReader::.cto...
How can I represent an 'Enum' in Python?
...34. Code is not perfectly compatible between py2 and py3, e.g. you'll need __order__ in python 2).
To use enum34, do $ pip install enum34
To use aenum, do $ pip install aenum
Installing enum (no numbers) will install a completely different and incompatible version.
from enum import Enum #...
MySQL: What's the difference between float and double?
...00002 | 1.6900000000 |
This is using MySQL 6.7
Query:
SELECT
float_1 + float_2 as 'float add',
double_1 + double_2 as 'double add',
decimal_1 + decimal_2 as 'decimal add',
float_1 * float_2 as 'float multiply',
double_1 * double_2 as 'double multiply',
decimal_1 * decim...
Django select only rows with duplicate field values
...values('name')
.annotate(Count('id'))
.order_by()
.filter(id__count__gt=1)
This is as close as you can get with Django. The problem is that this will return a ValuesQuerySet with only name and count. However, you can then use this to construct a regula...
Elastic Search: how to see the indexed data
...Search and Rails, where some data was not indexed properly because of attr_protected. Where does Elastic Search store the indexed data? It would be useful to check if the actual indexed data is wrong.
...
From an array of objects, extract value of a property as array
...
Check out Lodash's _.pluck() function or Underscore's _.pluck() function. Both do exactly what you want in a single function call!
var result = _.pluck(objArray, 'foo');
Update: _.pluck() has been removed as of Lodash v4.0.0, in favour of _...
Arduino 101 实验06 - 土壤湿度传感器，做一个浇水提醒 · App Inventor 2 中文网
...
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sql “LIKE” equivalent in django query
...
Use __contains or __icontains (case-insensitive):
result = table.objects.filter(string__contains='pattern')
The SQL equivalent is
SELECT ... WHERE string LIKE '%pattern%';
...
Get event listeners attached to node using addEventListener
... 'old' prototype methods):
var ListenerTracker=new function(){
var is_active=false;
// listener tracking datas
var _elements_ =[];
var _listeners_ =[];
this.init=function(){
if(!is_active){//avoid duplicate call
intercep_events_listeners();
}
...
How to do relative imports in Python?
...answering the question.
The problem is that you're running the module as '__main__' by passing the mod1.py as an argument to the interpreter.
From PEP 328:
Relative imports use a module's __name__ attribute to determine that module's position in the package hierarchy. If the module's name does...