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Checking whether a variable is an integer or not [duplicate]
...er the right answer in Python, since it blocks all the flexibility of polymorphism. For instance, if you subclass int, your new class should register as an int, which type will not do:
class Spam(int): pass
x = Spam(0)
type(x) == int # False
isinstance(x, int) # True
This adheres to Python's strong...
PHP Difference between array() and []
I'm writing a PHP app and I want to make sure it will work with no errors.
5 Answers
5...
How does Java Garbage Collection work with Circular References?
...bjects will be collected. Even though objects may point to each other to form a cycle, they're still garbage if they're cut off from the root.
See the section on unreachable objects in Appendix A: The Truth About Garbage Collection in Java Platform Performance: Strategies and Tactics for the gory ...
What does this square bracket and parenthesis bracket notation mean [first1,last1)?
...is means that end is exclusive and doesn't contain the listed element. So for [first1, last1), the range starts with first1 (and includes it), but ends just before last1.
Assuming integers:
(0, 5) = 1, 2, 3, 4
(0, 5] = 1, 2, 3, 4, 5
[0, 5) = 0, 1, 2, 3, 4
[0, 5] = 0, 1, 2, 3, 4, 5
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Ruby: kind_of? vs. instance_of? vs. is_a?
...s better sometimes. Think @honda.kind_of? Car and @person.is_a? Administrator, Ruby's all about the aesthetics. In fact, notice the grammatical error... with active support you can write @person.is_an? Administrator :)... That might have made it into Ruby core by now, actually.
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How to escape special characters in building a JSON string?
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A JSON string must be double-quoted, according to the specs, so you don't need to escape '.
If you have to use special character in your JSON string, you can escape it using \ character.
See this list of special character used in JSON :
\b Backspace (ascii code ...
What is the difference between require_relative and require in Ruby?
...t is relative to the file containing the require_relative statement.
For example, if you have unit test classes in the "test" directory, and data for them under the test "test/data" directory, then you might use a line like this in a test case:
require_relative "data/customer_data_1"
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Responsively change div size keeping aspect ratio [duplicate]
When I give an image a percent width or height only it will grow/shrink keeping its aspect ratio, but if I want the same effect with another element, is it possible at all to tie the width and the height together using percentage?
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Circle-Rectangle collision detection (intersection)
...ith the rectangle:
Either the circle's centre lies inside the rectangle, or
One of the edges of the rectangle has a point in the circle.
Note that this does not require the rectangle to be axis-parallel.
(One way to see this: if none of the edges has a point in the circle (if all the edges a...
Is MD5 still good enough to uniquely identify files?
...ood enough method to uniquely identify it given all the breaking of MD5 algorithm and security issues etc? Security is not my primary concern here, but uniquely identifying each file is.
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