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Count, size, length…too many choices in Ruby?
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In the case where you don't provide a parameter to count it has basically the same effect as calling length. There can be a performance difference though.
We can see from the source code for Array that they do almost exactly the same thing. Here is the C code for the implementation of array.l...
In MySQL queries, why use join instead of where?
...le about using strict typing whenever possible. Explicit is almost universally better.
Conclusion
Short of familiarity and/or comfort, I don't see any benefit to continuing to use the ANSI-89 WHERE clause instead of the ANSI-92 JOIN syntax. Some might complain that ANSI-92 syntax is more verb...
What to do with branch after merge
...he merge, it's safe to delete the branch:
git branch -d branch1
Additionally, git will warn you (and refuse to delete the branch) if it thinks you didn't fully merge it yet. If you forcefully delete a branch (with git branch -D) which is not completely merged yet, you have to do some tricks to ge...
How do I escape reserved words used as column names? MySQL/Create Table
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IMHO you should quote all field names and table names always.
– rjmunro
Sep 17 '13 at 11:50
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How do I embed a single file from a GitHub gist with the new gist interface?
...tHub Gist interface has one embed snippet for the entire gist which embeds all files in the gist. The old interface had embed code for each file in the gist. Anyone know if there's a trick to embed a single file?
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pinpointing “conditional jump or move depends on uninitialized value(s)” valgrind message
... use of uninitialised data in a way that might affect your program's externally-visible behaviour.
From the Valgrind FAQ:
As for eager reporting of copies of uninitialised memory values, this has been suggested multiple times. Unfortunately, almost all programs legitimately copy uninitialised ...
Android Fragments: When to use hide/show or add/remove/replace?
...n detached from the window so it's no longer visible. So you could technically still interact with the fragment and reattach its UI later you need to. If you replace the fragment, the you are actually pulling it out of the container and it will go through all of the teardown events in the lifecycl...
What's the difference between an exclusive lock and a shared lock?
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When the students are reading (shared locks) what is on the board:
They all can read what is on it, together => Multiple shared locks can co-exist.
The teacher waits for them to finish reading before she clears the board to write more => If one or more shared locks already exist, exclusive ...
How do I filter ForeignKey choices in a Django ModelForm?
... can populate the validation data by making using the super(...).__init__ call in your overridden method. If you are making several of these queryset changes its a lot more elegant to package them by overriding the init method.
– michael
Aug 7 '09 at 4:53
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prototype based vs. class based inheritance
...t around someone (not you) trying to make their idea sound like The Best.
All object oriented languages need to be able to deal with several concepts:
encapsulation of data along with associated operations on the data, variously known as data members and member functions, or as data and methods, ...