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How does Python 2 compare string and int? Why do lists compare as greater than numbers, and tuples g
... the expected way (lexicographic ordering for string, numeric ordering for integers).
When you order a numeric and a non-numeric type, the numeric type comes first.
>>> 5 < 'foo'
True
>>> 5 < (1, 2)
True
>>> 5 < {}
True
>>> 5 < [1, 2]
True
When you...
Node.js throws “btoa is not defined” error
...mmatic interface, it only provides command line utilities.
If you need to convert to Base64 you could do so using Buffer:
console.log(Buffer.from('Hello World!').toString('base64'));
Reverse (assuming the content you're decoding is a utf8 string):
console.log(Buffer.from(b64Encoded, 'base64').t...
Python: changing value in a tuple
...basically two ways of replacing a tuple's element at a given index. Either convert the tuple to a list, replace the element and convert back, or construct a new tuple by concatenation.
In [1]: def replace_at_index1(tup, ix, val):
...: lst = list(tup)
...: lst[ix] = val
...: ret...
Size of character ('a') in C/C++
...
In C, the type of a character constant like 'a' is actually an int, with size of 4 (or some other implementation-dependent value). In C++, the type is char, with size of 1. This is one of many small differences between the two languages.
...
How to disable GCC warnings for a few lines of code
...member the state of the diagnostics as of each push, and restore to that point at each pop. If a pop has no matching push, the command-line options are restored." -- from the GCC manual: gcc.gnu.org/onlinedocs/gcc/Diagnostic-Pragmas.html
– bobpaul
Jan 11 '13 at...
What's the difference between __PRETTY_FUNCTION__, __FUNCTION__, __func__?
...ng this wanted to see.
For GCC:
$ cat test.cpp
#include <iostream>
int main(int argc, char **argv)
{
std::cout << __func__ << std::endl
<< __FUNCTION__ << std::endl
<< __PRETTY_FUNCTION__ << std::endl;
}
$ g++ test.cpp
$ ./...
How to use clock() in C++
...
#include <iostream>
#include <cstdio>
#include <ctime>
int main() {
std::clock_t start;
double duration;
start = std::clock();
/* Your algorithm here */
duration = ( std::clock() - start ) / (double) CLOCKS_PER_SEC;
std::cout<<"printf: "<< ...
Undefined behavior and sequence points
What are "sequence points"?
5 Answers
5
...
Why does Oracle 9i treat an empty string as NULL?
... spot on. The most confusing situations arise when '' is being implicitely converted to a VARCHAR2, such as cast('' as char(1)) is null which is... surprisingly TRUE
– sehe
Jul 19 '13 at 15:17
...
What's the point of g++ -Wreorder?
...
Consider:
struct A {
int i;
int j;
A() : j(0), i(j) { }
};
Now i is initialized to some unknown value, not zero.
Alternatively, the initialization of i may have some side effects for which the order is important. E.g.
A(int n) : j(n++...