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How to implement has_many :through relationships with Mongoid and mongodb?
...uire multiple queries.
https://github.com/mongoid/mongoid/issues/544
Normally if you have a many-many relationship in a RDBMS you would model that differently in MongoDB using a field containing an array of 'foreign' keys on either side. For example:
class Physician
include Mongoid::Document
...
UITextView that expands to text using auto layout
I have a view that is laid out completely using auto layout programmatically. I have a UITextView in the middle of the view with items above and below it. Everything works fine, but I want to be able to expand UITextView as text is added. This should push everything below it down as it expands.
...
Bash Templating: How to build configuration files from templates with Bash?
...\}/defined $ENV{$1} ? $ENV{$1} : $&/eg' < template.txt
to replace all ${...} strings with corresponding enviroment variables (do not forget to export them before running this script).
For pure bash this should work (assuming that variables do not contain ${...} strings):
#!/bin/bash
while...
64 bit OS下int占几个字节？ - C/C++ - 清泛网 - 专注C/C++及内核技术
...混淆。int是由编程语言设计决定的，不受编译器的影响。__int64才是8位的。另外，指针是受编译器 OS影响的，3...int固定4字节，不要受64 bit的混淆。int是由编程语言设计决定的，不受编译器的影响。
__int64才是8位的。
另外，指...
error C2664:...No user-defined-conversion operator available that can ...
...can perform this conversion, or the operator cannot be callederror C2664: '__thiscall std::list<int,class std::allocator<int> >::std::list<int,class std::allocator<int> >(unsigned...error C2664: '__thiscall std::list<int,class std::allocator<int> >::std::list<int,class std::allocator<int> >(unsigned...
...VC\\INCLUDE\\iterator(93) : error C2039: “push_front”: 不是“std...
...VC\INCLUDE\iterator(93) : error C2039: “push_front”: 不是“std::vector”的成员...VC INCLUDE iterator(93) : error C2039: push_front:不是std::vector<_Ty>的成员 with [ _Ty=int ]错误代码：int ia[] = {1......VC\INCLUDE\iterator(93) : error C2039: “push_front”: 不是“std:...
MFC SetCursor设置手型鼠标光标 - C/C++ - 清泛网 - 专注C/C++及内核技术
...部分代码如下：void CxxxDlg::OnMouseMove(UINT nFlags, CPoint point){__super::OnMouseMove(nFlags, point);int...设置手型鼠标光标，部分代码如下：
void CxxxDlg::OnMouseMove(UINT nFlags, CPoint point)
{
__super::OnMouseMove(nFlags, point);
int nIndex = HitTest(point);
if...
Call a python function from jinja2
I am using jinja2, and I want to call a python function as a helper, using a similar syntax as if I were calling a macro. jinja2 seems intent on preventing me from making a function call, and insists I repeat myself by copying the function into a template as a macro.
...
Setting an int to Infinity in C++
...or 2 147 483 647) if int is 32 bits wide on your implementation.
If you really need infinity, use a floating point number type, like float or double. You can then get infinity with:
double a = std::numeric_limits<double>::infinity();
...
Characters allowed in a URL
...
The characters allowed in a URI are either reserved or unreserved (or a percent character as part of a percent-encoding)
http://en.wikipedia.org/wiki/Percent-encoding#Types_of_URI_characters
says these are RFC 3986 unreserved characters ...