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

... Look at the widgets documentation. Basically it would look like: q = forms.CharField(label='search', widget=forms.TextInput(attrs={'placeholder': 'Search'})) More writing, yes, but the separation allows for better abstraction of more complic...
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How can I calculate the difference between two dates?

... Not all days have 86400 seconds. For a trivial example that's fine but it's not a good idea in the real world. DST changes, leap seconds, etc can all mess with it. NSCalendar can tell you how many seconds are in a given day. ...
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How do I get the result of a command in a variable in windows?

... If you have to capture all the command output you can use a batch like this: @ECHO OFF IF NOT "%1"=="" GOTO ADDV SET VAR= FOR /F %%I IN ('DIR *.TXT /B /O:D') DO CALL %0 %%I SET VAR GOTO END :ADDV SET VAR=%VAR%!%1 :END All output lines are stor...
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Store JSON object in data attribute in HTML jQuery

...in the text just use $('#myElement').data('key',jsonObject); it won't actually be stored in the html, but if you're using jquery.data, all that is abstracted anyway. To get the JSON back don't parse it, just call: var getBackMyJSON = $('#myElement').data('key'); If you are getting [Object Objec...
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What do commas and spaces in multiple classes mean in CSS?

..._12 .grid_6, .container_16 .grid_8 { width: 460px; } That says "make all .grid_6's within .container_12's and all .grid_8's within .container_16's 460 pixels wide." So both of the following will render the same: <div class="container_12"> <div class="grid_6">460px Wide</div&g...
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What is the “N+1 selects problem” in ORM (Object-Relational Mapping)?

The "N+1 selects problem" is generally stated as a problem in Object-Relational mapping (ORM) discussions, and I understand that it has something to do with having to make a lot of database queries for something that seems simple in the object world. ...
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Why can't I overload constructors in PHP?

I have abandoned all hope of ever being able to overload my constructors in PHP, so what I'd really like to know is why . ...
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Defining private module functions in python

...s, a simple #define private public line before #includeing your .h file is all it takes for wily coders to make hash of your "privacy"...!-)) share | improve this answer | fo...
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Is there a way to create a function from a string with javascript?

...github.com/reduardo7/sjsClass Example Class.extend('newClassName', { __constructor: function() { // ... } }); var x = new newClassName(); // Next is TRUE newClassName.name === 'newClassName' share ...
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How to get the number of Characters in a String?

..."), utf8.RuneCountInString("世界")) } Phrozen adds in the comments: Actually you can do len() over runes by just type casting. len([]rune("世界")) will print 2. At leats in Go 1.3. And with CL 108985 (May 2018, for Go 1.11), len([]rune(string)) is now optimized. (Fixes issue 24923) The compile...