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“Notice: Undefined variable”, “Notice: Undefined index”, and “Notice: Undefined offset” using PHP
...uses the same variable name. It is also a major security risk with register_globals turned on. E_NOTICE level error is issued in case of working with uninitialized variables, however not in the case of appending elements to the uninitialized array. isset() language construct can be used to detect if...
Can “list_display” in a Django ModelAdmin display attributes of ForeignKey fields?
...ion, you can do look ups like:
class UserAdmin(admin.ModelAdmin):
list_display = (..., 'get_author')
def get_author(self, obj):
return obj.book.author
get_author.short_description = 'Author'
get_author.admin_order_field = 'book__author'
...
Why can't I overload constructors in PHP?
...private constructor.
For example:
public MyClass {
private function __construct() {
...
}
public static function makeNewWithParameterA($paramA) {
$obj = new MyClass();
// other initialization
return $obj;
}
public static function makeNewWithParam...
How do you properly determine the current script directory in Python?
...
os.path.dirname(os.path.abspath(__file__))
is indeed the best you're going to get.
It's unusual to be executing a script with exec/execfile; normally you should be using the module infrastructure to load scripts. If you must use these methods, I suggest ...
What's the common practice for enums in Python? [duplicate]
...
@Joan You could do _unused, Shaded, Shiny, Transparent, Matte = range(5)
– zekel
Dec 9 '10 at 2:12
81
...
SQL Server Index Naming Conventions [closed]
...me indexes for SQL Server? It seems that the primary key index is named PK_ and non-clustered indexes typically start with IX_. Are there any naming conventions beyond that for unique indexes?
...
Preserving signatures of decorated functions
...nstall decorator module:
$ pip install decorator
Adapt definition of args_as_ints():
import decorator
@decorator.decorator
def args_as_ints(f, *args, **kwargs):
args = [int(x) for x in args]
kwargs = dict((k, int(v)) for k, v in kwargs.items())
return f(*args, **kwargs)
@args_as_int...
[精华]VC++对话框程序打印及打印预览的实现 - C/C++ - 清泛网 - 专注C/C++及内核技术
...程序文件菜单中会生成两个菜单项分别是打印（标识符ID_FILE_PRINT）和打印预览(标识符：ID_FILE_PRINT_PREVIEW)，展开程序源代码，可以发现，是CVIEW类提供标准打印和打印预览菜单命令的消息处理函数：
设应用程序视图类为CMyView,展...
Scala how can I count the number of occurrences in a list
...", "banana", "apple", "oranges", "oranges")
s.groupBy(identity).mapValues(_.size)
giving a Map with a count for each item in the original sequence:
Map(banana -> 1, oranges -> 3, apple -> 3)
The question asks how to find the count of a specific item. With this approach, the solution w...
Forced naming of parameters in Python
...ition to other good answers for Python 2, please consider the following:
__named_only_start = object()
def info(param1,param2,param3,_p=__named_only_start,spacing=10,collapse=1):
if _p is not __named_only_start:
raise TypeError("info() takes at most 3 positional arguments")
return...