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Why doesn't django's model.save() call full_clean()?
... if anyone knows if there's good reason why django's orm doesn't call 'full_clean' on a model unless it is being saved as part of a model form.
...
第一个Hello,OS World操作系统 - 操作系统(内核) - 清泛网 - 专注C/C++及内核技术
第一个Hello,OS World操作系统hello_os_word_my_first_os操作系统并非我们想象中的深不可测、遥不可及，只要你对它感兴趣并随我一起动手实践，你也能开发出属于自己的os。本文通过一个最简单的os，完成Hello, OS World文字的输出来演示os...
How to tell if a tag failed to load
... };
var fail = function () {
if (!scriptTag.__es) {
scriptTag.__es = true;
scriptTag.id = 'failed';
args.failure(scriptTag);
}
};
scriptTag.onload = function () {
...
How can I check if a Perl array contains a particular value?
...
Simply turn the array into a hash:
my %params = map { $_ => 1 } @badparams;
if(exists($params{$someparam})) { ... }
You can also add more (unique) params to the list:
$params{$newparam} = 1;
And later get a list of (unique) params back:
@badparams = keys %params;
...
How to make the 'cut' command treat same sequental delimiters as one?
...re. You could pass < text.txt directly to tr. en.wikipedia.org/wiki/Cat_%28Unix%29#Useless_use_of_cat
– arielf
Aug 9 '14 at 20:10
1
...
Random Gaussian Variables
...uller polar method:
public sealed class GaussianRandom
{
private bool _hasDeviate;
private double _storedDeviate;
private readonly Random _random;
public GaussianRandom(Random random = null)
{
_random = random ?? new Random();
}
/// <summary>
/// Obta...
undefined reference to `WinMain@16'
...>
int main()
{
MessageBox( 0, "Blah blah...", "My Windows app!", MB_SETFOREGROUND );
}
Now let's build it using GNU toolchain (i.e. g++), no special options. Here gnuc is just a batch file that I use for that. It only supplies options to make g++ more standard:
C:\test> gnuc x.cpp
C:...
Why not inherit from List?
...football to fill in the blank:
A football team is a particular kind of _____
Did anyone say "list of football players with a few bells and whistles", or did they all say "sports team" or "club" or "organization"? Your notion that a football team is a particular kind of list of players is in y...
Linq to Sql: Multiple left outer joins
...SQL:
Dim db As New ContractDataContext()
Dim query = From o In db.Orders _
Group Join v In db.Vendors _
On v.VendorNumber Equals o.VendorNumber _
Into ov = Group _
From x In ov.DefaultIfEmpty() _
Group Join s In db.Status _
On...
How do I install an R package from source?
...hen use install.packages() and set the repos=NULL:
install.packages(path_to_file, repos = NULL, type="source")
Where path_to_file would represent the full path and file name:
On Windows it will look something like this: "C:\\RJSONIO_0.2-3.tar.gz".
On UNIX it will look like this: "/home/blah/R...