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Difference between string and text in rails?
... load varchar in one go, but store text (and blob) outside of the table. A SELECT name, amount FROM products could, be a lot slower when using text for name than when you use varchar. And since Rails, by default loads records with SELECT * FROM... your text-columns will be loaded. This will probably...
What are transparent comparators?
...ast, works for std::string which has overloaded less than operators taking char const* as argument. Since these function objects are also new, even if they do the wrong thing (i.e. require a conversion for some type) it would, at least, not be a silent change resulting in a performance degradation.
...
Finding the max value of an attribute in an array of objects
...nput in a array):
var maxA = a.reduce((a,b)=>a.y>b.y?a:b).y; // 30 chars time complexity: O(n)
var maxB = a.sort((a,b)=>b.y-a.y)[0].y; // 27 chars time complexity: O(nlogn)
var maxC = Math.max(...a.map(o=>o.y)); // 26 chars time complexity: >O(2n)
editable example her...
Reverse a string in Java
...
This won't work for Unicode characters outside of BMP, as long as for combining characters.
– nau
Aug 17 '18 at 11:36
2
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Regular expression to get a string between two strings in Javascript
...ng pattern. However, a dot . in JavaScript regex does not match line break characters, so, what will work in 100% cases is a [^] or [\s\S]/[\d\D]/[\w\W] constructs.
ECMAScript 2018 and newer compatible solution
In JavaScript environments supporting ECMAScript 2018, s modifier allows . to match any c...
Can I convert a C# string value to an escaped string literal
... If you have a file with text containg escape sequences incluidng especial character escaped with its ascii code ? How to produce a raw version ?
– Luciano
Nov 29 '12 at 16:57
1
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What does {0} mean when initializing an object?
... initialized shall be
default-initialized.
Example:
struct S { int a; char* b; int c; };
S ss = { 1, "asdf" };
initializes ss.a with 1, ss.b with
"asdf", and ss.c with the value of an
expression of the form int(), that is,
0.
You can find the complete spec on this topic here
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How to initialize all members of an array to the same value?
...8(...) STRUCTVAL_32(__VA_ARGS__), STRUCTVAL_16(__VA_ARGS__)
struct Pair { char key[16]; char val[32]; };
struct Pair p_data[] = { STRUCTVAL_48("Key", "Value") };
int a_data[][4] = { STRUCTVAL_48(12, 19, 23, 37) };
macro names are negotiable.
...
C++ convert hex string to signed integer
...iostream>
using namespace std;
int main() {
string s = "abcd";
char * p;
long n = strtol( s.c_str(), & p, 16 );
if ( * p != 0 ) { //my bad edit was here
cout << "not a number" << endl;
}
else {
cout << n << endl;
}
}
...
Why is “int i = 2147483647 + 1;” OK, but “byte b = 127 + 1;” is not compilable?
... if the expression is a constant expression (§15.28) of type byte, short, char or int :
A narrowing primitive conversion may be used if the type of the variable is byte, short, or char, and the value of the constant expression is representable in the type of the variable.
Without this clause, ...