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Fastest way to get the first object from a queryset in django?
...'m pretty sure you'll even see this add LIMIT 1 to the query, and I don't know that you can do any better than this. However, internally __nonzero__ in QuerySet is implemented as try: iter(self).next() except StopIteration: return false... so it doesn't escape the exception.
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When should you use constexpr capability in C++11?
...t b ) { return a * b; }
const int meaningOfLife = MeaningOfLife( 6, 7 );
Now you have something that can be evaluated down to a constant while maintaining good readability and allowing slightly more complex processing than just setting a constant to a number.
It basically provides a good aid to ma...
#ifdef #ifndef in Java
...with "final" modifier Java compiler itself solves the problem. Because it knows in advance what would be the result of testing this condition.
For example this code:
boolean flag1 = true;
boolean flag2 = false;
int j=0;
for(int i=0;i<1000000000;i++){
if(flag1)
...
Callback when CSS3 transition finishes
...ore times than you were expecting. I am not aware of any work-around as of now.
– Lev
Dec 16 '13 at 20:25
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PHP YAML Parsers [closed]
Does anyone know of a good YAML Parser for PHP? If so, what are the pros and cons of this library?
8 Answers
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generate model using user:references vs user_id:integer
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how does rails know that user_id is a foreign key referencing user?
Rails itself does not know that user_id is a foreign key referencing user. In the first command rails generate model Micropost user_id:integer it only adds a column user_i...
Several ports (8005, 8080, 8009) required by Tomcat Server at localhost are already in use
...ch is using about 400 MB or more RAM will also solve the problem. It is unknowingly reserving the process.
– viper
Jun 10 '16 at 7:00
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What is a 'semantic predicate' in ANTLR?
... instead of a parser rule) that will match numbers in the range of 0..999. Now in the parser, you'd like to make a distinction between low- and hight numbers (low: 0..500, high: 501..999). This could be done using a disambiguating semantic predicate where you inspect the token next in the stream (in...
Is ASCII code 7-bit or 8-bit?
...he 8th bit of each byte of text for its own purposes ("not 8-bit clean"). Nowadays people think of it as an 8-bit coding in which bytes 0x80 through 0xFF have no defined meaning, but that's a retcon.
There are dozens of text encodings that make use of the 8th bit; they can be classified as ASCII-c...
Should “node_modules” folder be included in the git repository
...doing so as listed in context of accepted answer are pretty outdated as of now.
Published packages can't be revoked from npm registry that easily anymore. So you don't have to fear loosing dependencies your project has relied on before.
Putting package-json.lock file in VCS is helping with frequen...