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Check if a class is derived from a generic class
...on avoids the unnecessary recursion performance hit also. It's an elegant and beautiful solution to a meta-generic question.
– EnocNRoll - AnandaGopal Pardue
Jan 19 '09 at 18:26
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How can I record a Video in my Android App.?
How can I capture a video recording on Android?
10 Answers
10
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What is a stack trace, and how can I use it to debug my application errors?
...ject.Book.getTitle(Book.java:16)
To debug this, we can open up Book.java and look at line 16, which is:
15 public String getTitle() {
16 System.out.println(title.toString());
17 return title;
18 }
This would indicate that something (probably title) is null in the above code.
Exam...
Optimise PostgreSQL for fast testing
.... For example, PostgreSQL 9.2 significantly improves the speed of TRUNCATE and of course adds index-only scans. Even minor releases should always be followed; see the version policy.
Don'ts
Do NOT put a tablespace on a RAMdisk or other non-durable storage.
If you lose a tablespace the whole datab...
Using Kafka as a (CQRS) Eventstore. Good idea?
... events in the stream. Each Kafka topic consists of one or more partitions and each partition is stored as a directory on the file system. There will also be pressure from ZooKeeper as the number of znodes increases.
share
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Pointers vs. values in parameters and return values
...n doubt, use a pointer."
Slices, maps, channels, strings, function values, and interface values are implemented with pointers internally, and a pointer to them is often redundant.
Elsewhere, use pointers for big structs or structs you'll have to change, and otherwise pass values, because getting thi...
std::wstring VS std::string
I am not able to understand the differences between std::string and std::wstring . I know wstring supports wide characters such as Unicode characters. I have got the following questions:
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What's the best way to communicate between view controllers?
Being new to objective-c, cocoa, and iPhone dev in general, I have a strong desire to get the most out of the language and the frameworks.
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Class does not implement its superclass's required members
So I updated to Xcode 6 beta 5 today and noticed I received errors in nearly all of my subclasses of Apple's classes.
4 Ans...
Is git's semi-secret empty tree object reliable, and why is there not a symbolic name for it?
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So I guess it is safer to define a variable with the result of that command as your empty sha1 tree (instead of relying of a "well known value").
Note: Git 2.25.1 (Feb. 2020) proposes in commit 9c8a294:
empty_tree=$(git mktree </dev/null)
# Windows:
git mktree <NUL
And adds:
As a hi...