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Why #define TRUE (1==1) in a C boolean macro instead of simply as 1?
...type (and resolve to true and false) if the compiler supports it. (specifically, C++)
However, it would be better to check whether C++ is in use (via the __cplusplus macro) and actually use true and false.
In a C compiler, this is equivalent to 0 and 1.
(note that removing the parentheses will bre...
How to turn on/off ReactJS 'development mode'?
...me helpers off during production. Just using the minified react will leave all those potential optimizations on the table as well.
Ultimately the magic comes down to React embedding references to process.env.NODE_ENV throughout the codebase; these act like a feature toggle.
if (process.env.NODE_ENV ...
Preloading images with JavaScript
Is the function I wrote below enough to preload images in most, if not all, browsers commonly used today?
14 Answers
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Macro vs Function in C
...uct webpage page;
page.numButtons = 2;
num_button_holes(page) -> 8
Finally, macros can be difficult to debug, producing weird syntax errors or runtime errors that you have to expand to understand (e.g. with gcc -E), because debuggers cannot step through macros, as in this example:
#define prin...
Is cout synchronized/thread-safe?
...f particular interest here is the fact that cout is buffered. Even if the calls to write (or whatever it is that accomplishes that effect in that particular implementation) are guaranteed to be mutually exclusive, the buffer might be shared by the different threads. This will quickly lead to corrupt...
Google Maps: how to get country, state/province/region, city given a lat/long value?
...
What you are looking for is called reverse geocoding. Google provides a server-side reverse geocoding service through the Google Geocoding API, which you should be able to use for your project.
This is how a response to the following request would look ...
Export specific rows from a PostgreSQL table as INSERT SQL script
....5.3, and my create statement was the same as yours except create view.... All I get in the output is the usual pg_dump comments and SET statements. Not sure where I'm going wrong.
– poshest
Nov 20 '16 at 15:19
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Dealing with commas in a CSV file
...any easily-available csv library - that is to say RFC 4180.
There's actually a spec for CSV format and how to handle commas:
Fields containing line breaks (CRLF), double quotes, and commas should be enclosed in double-quotes.
http://tools.ietf.org/html/rfc4180
So, to have values foo and ...
do N times (declarative syntax)
...based on Array.forEach, without any library, just native vanilla.
To basically call something() 3 times, use:
[1,2,3].forEach(function(i) {
something();
});
considering the following function:
function something(){ console.log('something') }
The outpout will be
something
something
somethi...
Locking a file in Python
...terminate in such a way that the lock is left in place and you have to manually delete the lock before the file becomes accessible again. However, that aside, this is still a good solution.
– leetNightshade
Nov 8 '12 at 21:27
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