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Still Reachable Leak detected by Valgrind
...d are almost always leaks.
Here is an example
int foo(void)
{
static char *working_buf = NULL;
char *temp_buf;
if (!working_buf) {
working_buf = (char *) malloc(16 * 1024);
}
temp_buf = (char *) malloc(5 * 1024);
....
....
....
}
Valgrind will report wo...
What is the difference between ? and Object in Java generics?
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An instance of HashMap<String, String> matches Map<String, ?> but not Map<String, Object>. Say you want to write a method that accepts maps from Strings to anything: If you would write
public void foobar(Map<String, Object> ms...
find() with nil when there are no records
...ou already have a block such as a controller method. In that case the only extra line you need is the rescue line. Much more elegant and easier to handle than checking for nil with an if statement.
– morgler
Aug 1 '17 at 7:30
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When saving, how can you check if a field has changed?
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Really perfect, and do not perform extra query. Thanks a lot !
– Stéphane
Mar 4 '13 at 10:26
29
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How to remove the first character of string in PHP?
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To remove every : from the beginning of a string, you can use ltrim:
$str = '::f:o:';
$str = ltrim($str, ':');
var_dump($str); //=> 'f:o:'
share
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improve this ...
Polymorphism in C++
...on, loop unrolling, static stack-based arrays vs heap)
__FILE__, __LINE__, string literal concatenation and other unique capabilities of macros (which remain evil ;-))
templates and macros test semantic usage is supported, but don't artificially restrict how that support is provided (as virtual disp...
Postgresql aggregate array
...
What I understand you can do something like this:
SELECT p.p_name,
STRING_AGG(Grade.Mark, ',' ORDER BY Grade.Mark) As marks
FROM Student
LEFT JOIN Grade ON Grade.Student_id = Student.Id
GROUP BY Student.Name;
EDIT
I am not sure. But maybe something like this then:
SELECT p.p_name,
...
Check if a value is in an array (C#)
...y namespace
using System.Linq;
Then you can use linq Contains() method
string[] printer = {"jupiter", "neptune", "pangea", "mercury", "sonic"};
if(printer.Contains("jupiter"))
{
Process.Start("BLAH BLAH CODE TO ADD PRINTER VIA WINDOWS EXEC"");
}
...
How to store a list in a column of a database table
...ding on localization), and stitch those together. Otherwise we'd not store strings of text at all. On the other hand, all he wants is a string of strings. And there are ways to do that.
– Haakon Løtveit
May 25 '17 at 9:36
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Why “decimal” is not a valid attribute parameter type?
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OK so why are strings allowed as attribute properties? I suppose it comes under the 'array of primitives' category but it is heap allocated (reference type)...
– Steztric
Nov 11 '16 at 8:29
...