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How can I clear scrollback buffer in Tmux?
...ve at the state to enter the clear-history command, press Ctrl+B, and then start the command with a colon (:).
– palswim
May 19 '14 at 23:11
2
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AngularJS : Where to use promises?
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Even in this case, which is only chaining together two operations, things start to get messy. The method askFacebookForAuthentication accepts a callback for failure and success, but what happens when FB.login succeeds but FB.api fails? This method always invokes the success callback regardless of...
How can I reset or revert a file to a specific revision?
...l-known to be scary/dangerous. But, the point is, in *nix a file name can start with a '-', and this will confuse various commandline interpreters which, when they see a '-', expect a command option to follow. It could be any file starting with '-'; e.g., "-mySpecialFile".
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Exception thrown in catch and finally clause
... forgotten) as the new exception is propagated outward. The new exception starts unwinding up the stack just like any other exception, aborting out of the current block (the catch or finally block) and subject to any applicable catch or finally blocks along the way.
Note that applicable catch or f...
how to use sed, awk, or gawk to print only what is matched?
...the character position, or index, of where that substring begins (1, if it starts at the beginning of string), it triggers the print action.
With grep you can use a look-behind and look-ahead:
$ grep -oP '(?<=abc)[0-9]+(?=xyz)' file
12345
$ grep -oP 'abc\K[0-9]+(?=xyz)' file
12345
This che...
Changing default encoding of Python?
..., since sys.setdefaultencoding() is purposely removed from sys when Python starts. Reenabling it and changing the default encoding can break code that relies on ASCII being the default (this code can be third-party, which would generally make fixing it impossible or dangerous).
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Determining the size of an Android view at runtime
... in onPostCreate() which gets run after the view is completely created and started.
– Nik Reiman
Sep 24 '10 at 7:39
1
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Retrieve only the queried element in an object array in MongoDB collection
...d({"shapes.color": "red"}, {_id: 0, 'shapes.$': 1});
MongoDB 3.2 Update
Starting with the 3.2 release, you can use the new $filter aggregation operator to filter an array during projection, which has the benefit of including all matches, instead of just the first one.
db.test.aggregate([
// ...
How do I make a list of data frames?
... don't wait until you have a bunch of a data.frames to add them to a list. Start with the list.
The rest of the this answer will cover some common cases where you might be tempted to create sequential variables, and show you how to go straight to lists. If you're new to lists in R, you might want t...
Error during installing HAXM, VT-X not working
...I downloaded appropriate file HAXM file for Windows 7 64 bit, unpacked and started installing. However, during the installation process I get this error:
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