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?: operator (the 'Elvis operator') in PHP
...m2' => 'value2',
'param3' => 'value3',];
$param1 = isset($params['param1'])?:null;
$param2 = !empty($params['param2'])?:null;
$param3 = $params['param3']?:null; // get E_NOTICE, if $params['param3'] eq false
var_dump($param1,$param2,$param3);
true // would like to expe...
Are static fields open for garbage collection?
Given an hypothetical utility class that is used only in program setup:
6 Answers
6
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If string is empty then return some default value
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Yes, it is bad idea to set defaults in models :) My forms will weep
– fl00r
Jan 27 '11 at 14:32
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How do you list all triggers in a MySQL database?
...ENCE_OLD_ROW
ACTION_REFERENCE_NEW_ROW
CREATED
SQL_MODE
DEFINER
CHARACTER_SET_CLIENT
COLLATION_CONNECTION
DATABASE_COLLATION
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-didSelectRowAtIndexPath: not being called
...wDelegate for that table view, though UITableViewController is supposed to set that automatically.
Any chance you reset the delegate to some other class?
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Debug vs. Release performance
...erformance. If you care about performance then the right thing to do is to set some performance goals and then write yourself a test suite which tracks your progress against those goals. Once you have a such a test suite you can then easily use it to test for yourself the truth or falsity of stateme...
Inject errors into already validated form?
...ting list:
from django.forms.utils import ErrorList
errors = form._errors.setdefault("myfield", ErrorList())
errors.append(u"My error here")
And if you want to add non-field errors, use django.forms.forms.NON_FIELD_ERRORS (defaults to "__all__") instead of "myfield".
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Keep only date part when using pandas.to_datetime
...atetime64 then you can just normalize the time component to midnight so it sets all the values to 00:00:00:
df['normalised_date'] = df['dates'].dt.normalize()
This keeps the dtype as datetime64, but the display shows just the date value.
pandas: .dt accessor
pandas.Series.dt
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Latex Remove Spaces Between Items in List
...t to remove the spacing globally for every list in your document just put \setlist[itemize]{noitemsep} in your preamble.
– Fabian Winkler
Mar 13 '13 at 15:52
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CSS margin terror; Margin adds space outside parent element [duplicate]
...utely positioned elements
inline-block elements
elements with overflow set to anything other than visible (They do not collapse margins with their children.)
cleared elements (They do not collapse their top margins with their parent block’s bottom margin.)
the root element
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