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In Django - Model Inheritance - Does it allow you to override a parent model's attribute?
...ld instances (at least,
not at the moment). If a base class has a field called author, you
cannot create another model field called author in any class that
inherits from that base class.
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Eclipse returns error message “Java was started but returned exit code = 1”
... message points to a problem with your Java version. Do you have a JDK installed?
Try adding the following (noting the new line):
/!\ make sure, that the -vm option occurs before the -vmargs command.
Everything after -vmargs is passed directly to the JVM.
-vm
c:/wherever/java/jdk1.6.0_21/...
Escape quotes in JavaScript
I'm outputting values from a database (it isn't really open to public entry, but it is open to entry by a user at the company -- meaning, I'm not worried about XSS ).
...
Why does this Java code compile?
...+ 1 is illegal because b is an illegal forward reference to b. You can actually fix this by writing int b = this.b + 1, which compiles without complaints.
For local variables, int d = d + 1 is illegal because d is not initialized before use. This is not the case for fields, which are always default...
How to check if a map contains a key in Go?
...ring) and ok will receive a bool that will be set to true if "foo" was actually present in the map
evaluates ok, which will be true if "foo" was in the map
If "foo" is indeed present in the map, the body of the if statement will be executed and val will be local to that scope.
...
What is the LD_PRELOAD trick?
...ibrary (including the C runtime, libc.so). So to run ls with your special malloc() implementation, do this:
$ LD_PRELOAD=/path/to/my/malloc.so /bin/ls
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How to validate an email address using a regular expression?
...he IP address pattern that is floating around the internet with a bug that allows 00 for any of the unsigned byte decimal values in a dot-delimited address, which is illegal. The rest of it appears to be consistent with the RFC 5322 grammar and passes several tests using grep -Po, including cases d...
Laravel migration: unique key is too long, even if specified
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Specify a smaller length for your e-mail:
$table->string('email', 250);
Which is the default, actually:
$table->string('email');
And you should be good.
For Laravel 5.4 you can find a solution in this Laravel 5.4: Specified ...
In Python, when should I use a function instead of a method?
...sulation which is so dear to OO design.
The encapsulation principal is really what this comes down to: as a designer you should hide everything about the implementation and class internals which it is not absolutely necessarily for any user or other developer to access. Because we deal with instan...
How to use a custom comparison function in Python 3?
...e a workaround, but I think I am going to lose some performance by passing all the comparison operators < > = to middle man, since my original custom sort is written in C , it had around 1/2x speed of default sort.
– YOU
Mar 28 '10 at 5:26
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