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When saving, how can you check if a field has changed?
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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...
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...
Append text to input field
...might want to write a function:
//Append text to input element
function jQ_append(id_of_input, text){
var input_id = '#'+id_of_input;
$(input_id).val($(input_id).val() + text);
}
After you can just call it:
jQ_append('my_input_id', 'add this text');
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Count how many records are in a CSV Python?
...aranteed to be a fixed size, so the only way to count them is to read them all.
– Martijn Pieters♦
Apr 19 '13 at 15:55
1
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What is a memory fence?
...ead/writes occur in the order you expect. For example a 'full fence' means all read/writes before the fence are comitted before those after the fence.
Note memory fences are a hardware concept. In higher level languages we are used to dealing with mutexes and semaphores - these may well be implemen...
How to reload a clojure file in REPL
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:reload-all should also work. The OP specifically says it doesn't, but I think there was something else wrong in the OP's dev environment because for a single file the two (:reload and :reload-all) should have the same effect. Here'...
How can you profile a Python script?
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Python includes a profiler called cProfile. It not only gives the total running time, but also times each function separately, and tells you how many times each function was called, making it easy to determine where you should make optimizations.
You c...
How to use clock() in C++
How do I call clock() in C++ ?
7 Answers
7
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How do I make calls to a REST api using C#?
...and this thread is one of the top results when doing a Google search for "call restful service c#".
Current guidance from Microsoft is to use the Microsoft ASP.NET Web API Client Libraries to consume a RESTful service. This is available as a NuGet package, Microsoft.AspNet.WebApi.Client. You will n...
Adding :default => true to boolean in existing Rails column
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change_column is a method of ActiveRecord::Migration, so you can't call it like that in the console.
If you want to add a default value for this column, create a new migration:
rails g migration add_default_value_to_show_attribute
Then in the migration created:
# That's the more generic way t...