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Why doesn't Java offer operator overloading?
...ment means to copy a reference to an existing value.
Consider instead:
b.set(1, 0); // initialize to real number '1'
a = b;
b.set(2, 0);
assert( !a.equals(b) ); // this assertion will fail
In C++, this copies the value, so the comparison will result not-equal. In Java, operator= performs refere...
Why not abstract fields?
...I could do that of course. And I had thought of it. But why do I have to set a value in the base class when I know for a fact that I'm going to override that value in every derived class? Your argument could also be used to argue that there is no value in allowing abstract methods either.
...
load and execute order of scripts
...ult a dynamically added script tag to async unless the script tag has been set otherwise.
A script tag with async may be run as soon as it is loaded. In fact, the browser may pause the parser from whatever else it was doing and run that script. So, it really can run at almost any time. If the ...
What does “coalgebra” mean in the context of programming?
...noids and so on. Most of the time, these things are introduced in terms of sets, but since we're among friends, I'll talk about Haskell types instead. (I can't resist using some Greek letters though—they make everything look cooler!)
An algebra, then, is just a type τ with some functions and ide...
creating a random number using MYSQL
...t to a variable and use the variable if you have master slave replication. SET @r=FLOOR(RAND() * 401) + 100, then SELECT @r.
– Qian Chen
Mar 23 '16 at 6:55
3
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An example of how to use getopts in bash
...e case of unsupported option, : in the case of missing value.
OPTARG - is set to current argument value,
OPTERR - indicates if Bash should display error messages.
So the code can be:
#!/usr/bin/env bash
usage() { echo "$0 usage:" && grep " .)\ #" $0; exit 0; }
[ $# -eq 0 ] && usa...
phpinfo() - is there an easy way for seeing it?
...
@JamesHalsall If you need to emulate the PHP settings that your web server is using, that's the proper way to do it. Otherwise you're either erroneously using the CLI settings, or you're removing the separation between CLI settings and web server settings. That separati...
Types in MySQL: BigInt(20) vs Int(20)
... |
+-------+------------------+------+-----+---------+-------+
1 row in set (0,00 sec)
mysql> INSERT INTO `test` (`id`) VALUES (401421228216);
ERROR 1264 (22003): Out of range value for column 'id' at row 1
mysql> SET sql_mode = '';
Query OK, 0 rows affected, 1 warning (0,00 sec)
mysql&g...
Remove leading or trailing spaces in an entire column of data
...k 'Text to columns' from the 'Data' tab, then choose option 'Fixed width'.
Set a break line so the longest text will fit. If your largest cell
has 100 characters you can set the breakline on 200 or whatever you
want.
Finish the operation.
You can now delete the new column Excel has created.
The 's...
.prop('checked',false) or .removeAttr('checked')?
...
jQuery 3
As of jQuery 3, removeAttr does not set the corresponding property to false anymore:
Prior to jQuery 3.0, using .removeAttr() on a boolean attribute such as checked, selected, or readonly would also set the corresponding named property to false. This behavior ...