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How do I add a placeholder on a CharField in Django?

...t specify the field (e.g. for some dynamic method), you can use this: def __init__(self, *args, **kwargs): super(MyForm, self).__init__(*args, **kwargs) self.fields['email'].widget.attrs['placeholder'] = self.fields['email'].label or 'email@address.nl' It also allows the placeholder to de...
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How to make inline functions in C#

...omitted a lot of class setup stuff) This is the Main function: IL_001f: stloc.0 IL_0020: ldstr "P1 = {0}" IL_0025: ldloc.0 IL_0026: ldc.i4.5 IL_0027: callvirt instance !1 class [mscorlib]System.Func`2<int32, int32>::Invoke(!0) IL_002c: box [msc...
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Calling Objective-C method from C++ member function?

...hat C++ class a objective-C function [context renderbufferStorage:GL_RENDERBUFFER fromDrawable:(CAEAGLLayer*)self.layer]; which I cannot do in C++ syntax. ...
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Using os.walk() to recursively traverse directories in Python

...!/usr/bin/env python # -*- coding: utf-8 -*- """FileTreeMaker.py: ...""" __author__ = "legendmohe" import os import argparse import time class FileTreeMaker(object): def _recurse(self, parent_path, file_list, prefix, output_buf, level): if len(file_list) == 0 \ or (self...
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Bring element to front using CSS

...ects. For example <div class="container"> <div class="branch_1"> <div class="branch_1__child"></div> </div> <div class="branch_2"> <div class="branch_2__child"></div> </div> </div> If you gave branch_1__c...
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Define a lambda expression that raises an Exception

... There is more than one way to skin a Python: y = lambda: (_ for _ in ()).throw(Exception('foobar')) Lambdas accept statements. Since raise ex is a statement, you could write a general purpose raiser: def raise_(ex): raise ex y = lambda: raise_(Exception('foobar')) But if...
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What is the documents directory (NSDocumentDirectory)?

...lowing tech note: https://developer.apple.com/library/ios/technotes/tn2406/_index.html The Apple sanctioned way (from the link above) is as follows: // Returns the URL to the application's Documents directory. - (NSURL *)applicationDocumentsDirectory { return [[[NSFileManager defaultManager] U...
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If table exists drop table then create it, if it does not exist just create it

...e and swap it with an old one (table contents are lost): CREATE TABLE `bla__new` (id int); /* if not ok: terminate, report error */ RENAME TABLE `bla__new` to `bla`; /* if ok: terminate, report success */ RENAME TABLE `bla` to `bla__old`, `bla__new` to `bla`; DROP TABLE IF EXISTS `bla__old`; You...
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How do I mock an open used in a with statement (using the Mock framework in Python)?

...ager (from the examples page in the mock documentation): >>> open_name = '%s.open' % __name__ >>> with patch(open_name, create=True) as mock_open: ... mock_open.return_value = MagicMock(spec=file) ... ... with open('/some/path', 'w') as f: ... f.write('something') ...
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Can we define implicit conversions of enums in c#?

...rmined from reflection /// </summary> private string _name; /// <summary> /// The DescriptionAttribute, if any, linked to the declaring field /// </summary> private DescriptionAttribute _descriptionAttribute; /// <summary...