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Error :Request header field Content-Type is not allowed by Access-Control-Allow-Headers
... extra header. Try prepending the following to your file if you are using PHP:
header("Access-Control-Allow-Origin: *");
header("Access-Control-Allow-Headers: Origin, X-Requested-With, Content-Type, Accept");
Make sure that you haven't already used header in another file, or you will get a nasty...
C++ preprocessor __VA_ARGS__ number of arguments
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This is actually compiler dependent, and not supported by any standard.
Here however you have a macro implementation that does the count:
#define PP_NARG(...) \
PP_NARG_(__VA_ARGS__,PP_RSEQ_N())
#define PP_NARG_(...) \
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How can I implement a tree in Python?
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I came across this answer via Google. This library is really nice. I especially love the ability to use the mixin class to make an tree of any object!
– Rÿck Nöthing
Mar 8 '19 at 1:21
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What is the most effective way for float and double comparison?
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Be extremely careful using any of the other suggestions. It all depends on context.
I have spent a long time tracing a bugs in a system that presumed a==b if |a-b|<epsilon. The underlying problems were:
The implicit presumption in an algorithm that if a==b and b==c then a==c.
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How do the likely/unlikely macros in the Linux kernel work and what is their benefit?
I've been digging through some parts of the Linux kernel, and found calls like this:
10 Answers
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Reimport a module in python while interactive
... Redefinitions of names will override the old definitions, so this is generally not a problem, but if the new version of a module does not define a name that was defined by the old version, the old definition is not removed.
If a module imports objects from another module using from ... import ..., ...
uint8_t vs unsigned char
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It documents your intent - you will be storing small numbers, rather than a character.
Also it looks nicer if you're using other typedefs such as uint16_t or int32_t.
share
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Odd behavior when Java converts int to byte?
...+ unsignedByte);
Would print out: "Signed: -1 Unsigned: 255"
What's actually happening here?
We are using bitwise AND to mask all of the extraneous sign bits (the 1's to the left of the least significant 8 bits.)
When an int is converted into a byte, Java chops-off the left-most 24 bits
111111...
Twig for loop for arrays with keys
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Not the answer you're looking for? Browse other questions tagged php arrays loops twig or ask your own question.
Weighted random numbers
...a weighted random numbers. I'm currently just banging my head against the wall and cannot figure this out.
7 Answers
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