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Performance of Find() vs. FirstOrDefault() [duplicate]
...ject an anonmyous data item just for compilation
List<\u003C\u003Ef__AnonymousType0<string>> source = Enumerable.ToList(Enumerable.Select(Enumerable.Range(0, 1000000), i =>
{
var local_0 = new
{
Name = Guid.NewGuid().ToString()
};
return local_...
How to correctly use the extern keyword in C
...ction prototypes:
//--------------------------------------
//Filename: "my_project.H"
extern int function_1(void);
static int function_2(void);
int function_3(void);
The header file can be used by the main source code as follows:
//--------------------------------------
//Filename: "my_pr...
Dictionaries and default values
...collections import defaultdict
a = defaultdict(lambda: "default", key="some_value")
a["blabla"] => "default"
a["key"] => "some_value"
You can pass any ordinary function instead of lambda:
from collections import defaultdict
def a():
return 4
b = defaultdict(a, key="some_value")
b['absent...
Why shouldn't I use mysql_* functions in PHP?
What are the technical reasons for why one shouldn't use mysql_* functions? (e.g. mysql_query() , mysql_connect() or mysql_real_escape_string() )?
...
Does Python support short-circuiting?
...ent, but you could also state things very succinctly:
In [171]: name = raw_input('Enter Name: ') or '<Unkown>'
Enter Name:
In [172]: name
Out[172]: '<Unkown>'
In other words, if the return value from raw_input is true (not an empty string), it is assigned to name (nothing changes); ...
MemoryCache does not obey memory limits in configuration
...tCurrentPressure()
{
int num = GC.CollectionCount(2);
SRef ref2 = this._sizedRef;
if ((num != this._gen2Count) && (ref2 != null))
{
this._gen2Count = num;
this._idx ^= 1;
this._cacheSizeSampleTimes[this._idx] = DateTime.UtcNow;
this._cacheSizeSamples[this._idx] = ref2...
Calculate difference in keys contained in two Python dictionaries
...nged values
(4) keys same in both and unchanged values
"""
def __init__(self, current_dict, past_dict):
self.current_dict, self.past_dict = current_dict, past_dict
self.set_current, self.set_past = set(current_dict.keys()), set(past_dict.keys())
self.intersect = s...
How to set or change the default Java (JDK) version on OS X?
...
First run /usr/libexec/java_home -V which will output something like the following:
Matching Java Virtual Machines (3):
1.8.0_05, x86_64: "Java SE 8" /Library/Java/JavaVirtualMachines/jdk1.8.0_05.jdk/Contents/Home
1.6.0_65-b14-462, x86_64: "Java SE...
Instagram how to get my user id from username?
...request is made with the url below:
https://www.instagram.com/{username}/?__a=1
E.g:
This url will get all information about a user whose username is therock
https://www.instagram.com/therock/?__a=1
Update i June-20-2019, the API is public now. No authentication required.
Update in Decembe...
Practical usage of setjmp and longjmp in C
...y to verify that).
#include <stdio.h>
#include <setjmp.h>
jmp_buf bufferA, bufferB;
void routineB(); // forward declaration
void routineA()
{
int r ;
printf("(A1)\n");
r = setjmp(bufferA);
if (r == 0) routineB();
printf("(A2) r=%d\n",r);
r = setjmp(buffer...