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How to determine whether an object has a given property in JavaScript
How can I determine whether an object x has a defined property y , regardless of the value of x.y ?
7 Answers
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In vim, how do I go back to where I was before a search?
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What if you searched and made a change?
– Costa
Jan 2 '15 at 15:29
2
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Android. Fragment getActivity() sometimes returns null
...error reports sometimes I see reports with NPE issue. I do not understand what is wrong with my code. On emulator and my device application works good without forcecloses, however some users get NullPointerException in fragment class when the getActivity() method is called.
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Check if inputs are empty using jQuery
...at I would like all fields to be filled in. If a field is clicked into and then not filled out, I would like to display a red background.
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How to remove Firefox's dotted outline on BUTTONS as well as links?
I can make Firefox not display the ugly dotted focus outlines on links with this:
25 Answers
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Saving utf-8 texts in json.dumps as UTF8, not as \u escape sequence
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Use the ensure_ascii=False switch to json.dumps(), then encode the value to UTF-8 manually:
>>> json_string = json.dumps("ברי צקלה", ensure_ascii=False).encode('utf8')
>>> json_string
b'"\xd7\x91\xd7\xa8...
How to ignore xargs commands if stdin input is empty?
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For GNU xargs, you can use the -r or --no-run-if-empty option:
--no-run-if-empty
-r If the standard input does not contain any nonblanks, do not run the command. Normally, the command is run once even if there is no input. This opti...
How do I clone a Django model instance object and save it to the database?
In the database, I want to add another object which is a copy of the object above.
13 Answers
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How to take MySQL database backup using MySQL Workbench?
How to take database backup using MySQL Workbench? Can we take backup in the following ways-
9 Answers
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Android customized button; changing text color
I made a button that changes the background drawable on different states, this way:
5 Answers
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