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switch / pattern matching idea
...is is less useful with open ended types, but when matching a discriminated union or tuples, it's very nifty. In F#, you expect people to pattern match, and it instantly makes sense.
The "problem" is that once you start using some functional concepts, it's natural to want to continue. However, leve...
Is “argv[0] = name-of-executable” an accepted standard or just a common convention?
...ed to by argv[0] represents the program name; argv[0][0] shall be the null character if the program name is not available from the host environment.
So no, it's only the program name if that name is available. And it "represents" the program name, not necessarily is the program name. The section b...
Python function overloading
...working with languages that can discriminate data types at
compile-time, selecting among the alternatives can occur at
compile-time. The act of creating such alternative functions for
compile-time selection is usually referred to as overloading a
function. (Wikipedia)
Python is a dynamical...
Can I concatenate multiple MySQL rows into one field?
...
You can use GROUP_CONCAT:
SELECT person_id, GROUP_CONCAT(hobbies SEPARATOR ', ')
FROM peoples_hobbies
GROUP BY person_id;
As Ludwig stated in his comment, you can add the DISTINCT operator to avoid duplicates:
SELECT person_id, GROUP_CONCAT(DISTINCT ...
How do I use valgrind to find memory leaks?
...ok at the C code I wrote too:
#include <stdlib.h>
int main() {
char* string = malloc(5 * sizeof(char)); //LEAK: not freed!
return 0;
}
Well, there were 5 bytes lost. How did it happen? The error report just says
main and malloc. In a larger program, that would be seriously trouble...
How to split a file into equal parts, without breaking individual lines? [duplicate]
...
this is a way better answer than the selected one
– smatthewenglish
Apr 28 '16 at 11:41
...
Best practices for circular shift (rotate) operations in C++
...lude <stdint.h> // for uint32_t
#include <limits.h> // for CHAR_BIT
// #define NDEBUG
#include <assert.h>
static inline uint32_t rotl32 (uint32_t n, unsigned int c)
{
const unsigned int mask = (CHAR_BIT*sizeof(n) - 1); // assumes width is a power of 2.
// assert ( (c<...
Get the generated SQL statement from a SqlCommand object?
... }
sql.AppendLine(";");
sql.AppendLine("select 'Return Value' = convert(varchar, @return_value);");
foreach (SqlParameter sp in sc.Parameters)
{
if ((sp.Direction == ParameterDirection.InputOutput) || (sp.Directi...
How do I count the number of occurrences of a char in a String?
...
Guava equivalent: int count = CharMatcher.is('.').countIn("a.b.c.d"); ...As answered by dogbane in a duplicate question.
– Jonik
Aug 12 '13 at 17:00
...
How to get the input from the Tkinter Text Widget?
...u don't want the last newline character.
Demo
See below demonstration that selects the characters in between the given positions with sliders:
try:
import tkinter as tk
except:
import Tkinter as tk
class Demo(tk.LabelFrame):
"""
A LabeFrame that in order to demonstrate the string r...