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Why do function pointer definitions work with any number of ampersands '&' or asterisks '*'?
...o an object. For pointers to ordinary functions, it is always redundant because of the implicit function-to-function-pointer conversion. In any case, this is why void (*p3_foo)() = &foo; works.
The unary *, when applied to a function pointer, yields the pointed-to function, just like it yield...
Heroku “psql: FATAL: remaining connection slots are reserved for non-replication superuser connectio
I'm developing an app on Heroku with a Postgresql backend. Periodically, I get this error message when trying to access the database, both from the CLI and from loading a page on the server:
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Objective-C implicit conversion loses integer precision 'NSUInteger' (aka 'unsigned long') to 'int'
...er in the "Foundation Data Types Reference":
When building 32-bit applications, NSUInteger is a 32-bit unsigned
integer. A 64-bit application treats NSUInteger as a 64-bit unsigned
integer.
To fix that compiler warning, you can either declare the local count variable as
NSUInteger count;
...
Apply CSS styles to an element depending on its child elements
...oking at jQuery. Its selectors work very well with 'containing' types. You can select the div, based on its child contents and then apply a CSS class to the parent all in one line.
If you use jQuery, something along the lines of this would may work (untested but the theory is there):
$('div:has(di...
Does async(launch::async) in C++11 make thread pools obsolete for avoiding expensive thread creation
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Question 1:
I changed this from the original because the original was wrong. I was under the impression that Linux thread creation was very cheap and after testing I determined that the overhead of function call in a new thread vs. a normal one is enormous. The overhead f...
Modify file in place (same dest) using Gulp.js and a globbing pattern
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As you suspected, you are making this too complicated. The destination doesn't need to be dynamic as the globbed path is used for the dest as well. Simply pipe to the same base directory you're globbing the src from, in this case "sass":
gulp.src("sass/**/*.scss")
.pi...
Inheritance and Overriding __init__ in python
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The book is a bit dated with respect to subclass-superclass calling. It's also a little dated with respect to subclassing built-in classes.
It looks like this nowadays:
class FileInfo(dict):
"""store file metadata"""
def __init__(self, filename=None):
super(FileInfo...
std::auto_ptr to std::unique_ptr
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You cannot do a global find/replace because you can copy an auto_ptr (with known consequences), but a unique_ptr can only be moved. Anything that looks like
std::auto_ptr<int> p(new int);
std::auto_ptr<int> p2 = p;
...
How do you use Mongoose without defining a schema?
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PS: You have to do thing.set(key, value) because thing.key=value doesn't work with this method, i.e. it doesn't persist changed into the database otherwise.
– laggingreflex
Mar 18 '15 at 2:48
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Give all the permissions to a user on a DB
...ls.
You should run this function as superuser and as regular as your application requires. An option would be to package this in a cron job that executes every day or every hour.
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