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How to convert a number to string and vice versa in C++
...o-number conversion and vice-versa are built in into the standard library. All the following functions are present in <string> (as per paragraph 21.5).
string to numeric
float stof(const string& str, size_t *idx = 0);
double stod(const string& str, size_t *id...
How to automatically convert strongly typed enum into int?
...
Strongly typed enums aiming to solve multiple problems and not only scoping problem as you mentioned in your question:
Provide type safety, thus eliminating implicit conversion to integer by integral promotion.
Specify underlying types.
Provide strong scoping.
Thus, it is imp...
E11000 duplicate key error index in mongodb mongoose
... null value.
In other words, a sparse index is ok with multiple documents all having null values.
sparse indexes
From comments:
Your error says that the key is named mydb.users.$email_1 which makes me suspect that you have an index on both users.email and users.local.email (The former being old an...
What's the recommended way to connect to MySQL from Go?
...ound but it is difficult to determine the different states of completeness and current maintenance. I don't have complicated needs, but I'd like to know what people are relying on, or what's the most standard solution to connect to MySQL.
...
Suppressing “is never used” and “is never assigned to” warnings in C#
I have a HTTPSystemDefinitions.cs file in C# project which basically describes the older windows ISAPI for consumption by managed code.
...
Throw HttpResponseException or return Request.CreateErrorResponse?
... // If no exception handler registered for the exception type, fallback to default handler
actionExecutedContext.Response = DefaultHandler(
actionExecutedContext.Exception.GetBaseException(), actionExecutedContext.Request
);
...
Conditional import of modules in Python
...mport simplejson as json as it is likely a newer (faster) version of the standard json module.
– Seppo Erviälä
Oct 20 '12 at 17:07
...
str performance in python
...
'%s' % 100000 is evaluated by the compiler and is equivalent to a constant at run-time.
>>> import dis
>>> dis.dis(lambda: str(100000))
8 0 LOAD_GLOBAL 0 (str)
3 LOAD_CONST 1 (100000)
...
What is RSS and VSZ in Linux memory management
...
RSS is the Resident Set Size and is used to show how much memory is allocated to that process and is in RAM. It does not include memory that is swapped out. It does include memory from shared libraries as long as the pages from those libraries are actually in memory. It does include all st...
Maven2: Best practice for Enterprise Project (EAR file)
...ur two dependencies for your EJB project and your WAR project.
So you actually have three maven projects here. One EJB. One WAR. One EAR that pulls the two parts together and creates the ear.
Deployment descriptors can be generated by maven, or placed inside the resources directory in the EAR pr...