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The 'json' native gem requires installed build tools
...on my windows 7 machine. Now I tried to install the JSON gem using the command, "gem install json" and got the following error.
...
Event system in Python
...raries to choose from, using very different terminology (events, signals, handlers, method dispatch, hooks, ...).
I'm trying to keep an overview of the above packages, plus the techniques mentioned in the answers here.
First, some terminology...
Observer pattern
The most basic style of event system ...
Is 'switch' faster than 'if'?
...ntly increase performance in some scenarios, is as general as a switch is, and does not result in greater generated code size. But to see that, your test code would need a LOT more branches to see any difference.
To answer your specific questions:
Clang generates one that looks like this:
test_s...
What to do about Eclipse's “No repository found containing: …” error messages?
...n Linux to which I added the subversive plugins, the m2e Maven integration and the Mylin connector for Trac. For the last couple of weeks I've been trying to install updates, and every time I get back a message like
...
What's the pythonic way to use getters and setters?
...
What's the pythonic way to use getters and setters?
The "Pythonic" way is not to use "getters" and "setters", but to use plain attributes, like the question demonstrates, and del for deleting (but the names are changed to protect the innocent... builtins):
valu...
counting number of directories in a specific directory
...he number of folders in a specific directory. I am using the following command, but it always provides an extra one.
15 An...
Python syntax for “if a or b or c but not all of them”
I have a python script that can receive either zero or three command line arguments. (Either it runs on default behavior or needs all three values specified.)
...
What is a race condition?
...
A race condition occurs when two or more threads can access shared data and they try to change it at the same time. Because the thread scheduling algorithm can swap between threads at any time, you don't know the order in which the threads will attempt to access the shared data. Therefore, the re...
Using group by on multiple columns
I understand the point of GROUP BY x .
2 Answers
2
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How to store arrays in MySQL?
...
The proper way to do this is to use multiple tables and JOIN them in your queries.
For example:
CREATE TABLE person (
`id` INT NOT NULL PRIMARY KEY,
`name` VARCHAR(50)
);
CREATE TABLE fruits (
`fruit_name` VARCHAR(20) NOT NULL PRIMARY KEY,
`color` VARCHAR(20),
`price` INT
)...