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Unique fields that allow nulls in Django
...pty string by providing your own customized model form for Foo with a clean_bar method that turns the empty string into None:
class FooForm(forms.ModelForm):
class Meta:
model = Foo
def clean_bar(self):
return self.cleaned_data['bar'] or None
class FooAdmin(admin.ModelAdmin...
Split a string by another string in C#
...
I actually ended up changing my answer to this for 2 reasons: #1: To handle the splits I want to do I would need to use Regex.Escape, because my split string will often contain asterisks, etc. #2: While this program I'm writing...
How to find keys of a hash?
...
There is function in modern JavaScript (ECMAScript 5) called Object.keys performing this operation:
var obj = { "a" : 1, "b" : 2, "c" : 3};
alert(Object.keys(obj)); // will output ["a", "b", "c"]
Compatibility details can be found here.
On the Mozilla site there is also a sn...
PHP array delete by value (not key)
...
Well, deleting an element from array is basically just set difference with one element.
array_diff( [312, 401, 15, 401, 3], [401] ) // removing 401 returns [312, 15, 3]
It generalizes nicely, you can remove as many elements as you like at the same time, if you want.
...
How to import CSV file data into a PostgreSQL table?
...rticle.
Solution paraphrased here:
Create your table:
CREATE TABLE zip_codes
(ZIP char(5), LATITUDE double precision, LONGITUDE double precision,
CITY varchar, STATE char(2), COUNTY varchar, ZIP_CLASS varchar);
Copy data from your CSV file to the table:
COPY zip_codes FROM '/path/to/csv/ZI...
What's the best way to inverse sort in scala?
...way of changing the sign, if you sort by some numeric value
list.sortBy(- _.size)
More generally, sorting may be done by method sorted with an implicit Ordering, which you may make explicit, and Ordering has a reverse (not the list reverse below)
You can do
list.sorted(theOrdering.reverse)
If...
How to capture no file for fs.readFileSync()?
...
Basically, fs.readFileSync throws an error when a file is not found. This error is from the Error prototype and thrown using throw, hence the only way to catch is with a try / catch block:
var fileContents;
try {
fileContents =...
mongoose vs mongodb (nodejs modules/extensions), which better? and why?
...ith can cause it to not save anything, w/o error. We have found that using all lowercase names works best. E.g. instead of doing something like mongooseInstace.model('MyCollection', { "_id": Number, "xyz": String }) it's better to do (even though the collection name is really MyCollection): mongoose...
Is there any way to post events to Google Analytics via server-side API? [closed]
... $aParams['qt'] = 0;
//Client ID
$aParams['cid'] = substr(md5($_SERVER['REMOTE_ADDR'].$_SERVER['HTTP_USER_AGENT']), 0, 8);
//User ID
//$aParams['uid'] = '';
//Session Control
//$aParams[''] = '';
//IP Override
$aParams['uip'] = $_SERVER['REMOTE_ADDR'];
//U...
Convert string to integer type in Go?
...64); err == nil {
fmt.Printf("i=%d, type: %T\n", i, i)
}
var i int
if _, err := fmt.Sscan(s, &i); err == nil {
fmt.Printf("i=%d, type: %T\n", i, i)
}
Output (if called with argument "123"):
i=123, type: int
i=123, type: int64
i=123, type: int
Parsing Custom strings
There is also a...