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What does addChildViewController actually do?
...s I've had to do is implement a custom container view controller - lets call it SideBarViewController - that swaps out which of several possible child view controllers it shows, almost exactly like a standard Tab Bar Controller . (It's pretty much a Tab Bar Controller but with a hideable side...
Why is whitespace sometimes needed around metacharacters?
...s a list of characters that separate tokens in BASH. These characters are called metacharacters and they are |, &, ;, (, ), <, >, space and tab. On the other hand, curly braces ({ and }) are just ordinary characters that make up words.
Omitting the second space before } will do, since &am...
How to force uninstallation of windows service
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One thing that has caught me out in the past is that if you have the services viewer running then that prevents the services from being fully deleted, so close that beforehand
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Python pandas Filtering out nan from a data selection of a column of strings
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Just drop them:
nms.dropna(thresh=2)
this will drop all rows where there are at least two non-NaN.
Then you could then drop where name is NaN:
In [87]:
nms
Out[87]:
movie name rating
0 thg John 3
1 thg NaN 4
3 mol Graham NaN
4 lob N...
Is a statically-typed full Lisp variant possible?
Is a statically-typed full Lisp variant possible? Does it even make sense for something like this to exist? I believe one of a Lisp language's virtues is the simplicity of its definition. Would static typing compromise this core principle?
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What are the Differences Between “php artisan dump-autoload” and “composer dump-autoload”?
...it different:
1) It will in fact use Composer for some stuff
2) It will call Composer with the optimize flag
3) It will 'recompile' loads of files creating the huge bootstrap/compiled.php
4) And also will find all of your Workbench packages and composer dump-autoload them, one by one.
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What does “hashable” mean in Python?
...y and a set member, because these data structures use the hash value internally.
All of Python’s immutable built-in objects are hashable, while no mutable containers (such as lists or dictionaries) are. Objects which are instances of user-defined classes are hashable by default; they all comp...
How to make PyCharm always show line numbers
I cannot seem to be able to find the setting to enable line numbers for all files, but I have to always right click and enable this on per file basis.
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Why can't enum's constructor access static fields?
...tatic fields and methods? This is perfectly valid with a class, but is not allowed with an enum.
5 Answers
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Is file append atomic in UNIX?
...ger (linux seems to have it set to 4096).
This assume that you're talking all fully POSIX-compliant components. For instance, this isn't true on NFS.
But assuming you write to a log file you opened in 'O_APPEND' mode and keep your lines (including newline) under 'PIPE_BUF' bytes long, you should ...