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When saving, how can you check if a field has changed?
...
Essentially, you want to override the __init__ method of models.Model so that you keep a copy of the original value. This makes it so that you don't have to do another DB lookup (which is always a good thing).
class Person(models.Model):
name = models.CharF...
How to paste yanked text into the Vim command line
...you know how to use them you cannot live without them.
Registers are basically storage locations for strings. Vim has many registers that work in different ways:
0 (yank register: when you use y in normal mode, without specifying a register, yanked text goes there and also to the default register...
Embedding DLLs in a compiled executable
...to embed resources in your assembly. It's available as NuGet package.
Install-Package Costura.Fody
After adding it to the project, it will automatically embed all references that are copied to the output directory into your main assembly. You might want to clean the embedded files by adding a tar...
snprintf and Visual Studio 2010
... the expected behavior for snprintf:
int snprintf( char* buffer, std::size_t buf_size, const char* format, ... );
Writes at most buf_size - 1 characters to a buffer. The resulting
character string will be terminated with a null character, unless
buf_size is zero. If buf_size is zero, nothi...
Switching between GCC and Clang/LLVM using CMake
...xt with the following contents:
SET (CMAKE_C_FLAGS_INIT "-Wall -std=c99")
SET (CMAKE_C_FLAGS_DEBUG_INIT "-g")
SET (CMAKE_C_FLAGS_MINSIZEREL_INIT "-Os -DNDEBUG")
SET (CMAKE_C_FLAGS_RELEASE_INIT "-O3 -DNDEBUG")
SET (CMAKE_C_FLAGS_RELWITHDEBINFO_INIT "-O2 -g")
SET (...
How can I create an object and add attributes to it?
...ant to make a "bunch class", a very simple one already exists in Python -- all functions can have arbitrary attributes (including lambda functions). So, the following works:
obj = someobject
obj.a = lambda: None
setattr(obj.a, 'somefield', 'somevalue')
Whether the loss of clarity compared to the...
CoInitialize浅析一 - 操作系统(内核) - 清泛网 - 专注C/C++及内核技术
... push [ebp+8] ; pvReserved
769B2A2E call _CoInitializeEx@8 ; CoInitializeEx(x,x)
769B2A33 pop ebp
769B2A34 retn 4
可以看到，其中的实现还是比较简单的，它只是简单地调用了CoInitializeEx，将第二个...
Print string to text file
...t_file.close()
If you use a context manager, the file is closed automatically for you
with open("Output.txt", "w") as text_file:
text_file.write("Purchase Amount: %s" % TotalAmount)
If you're using Python2.6 or higher, it's preferred to use str.format()
with open("Output.txt", "w") as text...
How to specify new GCC path for CMake
... path /usr/bin/gcc . But it is old, I need a new version of gcc. So I install a new version in a new path /usr/local/bin/gcc .
...
How to make return key on iPhone make keyboard disappear?
...ate after you init the textfield in the .m:
yourTextField = [[UITextField alloc] initWithFrame:yourFrame];
//....
//....
//Setting the textField's properties
//....
//The next line is important!!
yourTextField.delegate = self; //self references the viewcontroller or view your textField is on
...