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Difference between “or” and || in Ruby? [duplicate]
What's the difference between the or and || operators in Ruby? Or is it just preference?
8 Answers
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How do I pipe or redirect the output of curl -v?
For some reason the output always gets printed to the terminal, regardless of whether I redirect it via 2> or > or |. Is there a way to get around this? Why is this happening?
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Emacs: print key binding for a command or list all key bindings
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C-h f (or M-x describe-function) will show you the bindings for a command.
You are correct, C-h b (or M-x describe-bindings) will show you all bindings. C-h m (M-x describe-mode) is also handy to list bindings by mode.
You might a...
What happens to an open file handle on Linux if the pointed file gets moved or deleted
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If the file is moved (in the same filesystem) or renamed, then the file handle remains open and can still be used to read and write the file.
If the file is deleted, the file handle remains open and can still be used (This is not what some people expect). The file will ...
How can I quantify difference between two images?
... and calculate an element-wise (pixel-by-pixel) difference. Calculate the norm of the difference.
Option 2: Load both images. Calculate some feature vector for each of them (like a histogram). Calculate distance between feature vectors rather than images.
However, there are some decisions to make ...
Undefined, unspecified and implementation-defined behavior
What is undefined behavior in C and C++? What about unspecified behavior and implementation-defined behavior? What is the difference between them?
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Difference between decimal, float and double in .NET?
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float and double are floating binary point types. In other words, they represent a number like this:
10001.10010110011
The binary number and the location of the binary point are both encoded within the value.
decimal is a floating decimal point type. In other words, they represent...
How to validate a url in Python? (Malformed or not)
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django url validation regex (source):
import re
regex = re.compile(
r'^(?:http|ftp)s?://' # http:// or https://
r'(?:(?:[A-Z0-9](?:[A-Z0-9-]{0,61}[A-Z0-9])?\.)+(?:[A-Z]{2,6}\.?|[A-Z0-9-]{2,}\.?)|' #domain...
r'localhost|' #localhost...
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Initializing a struct to 0
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The first is easiest(involves less typing), and it is guaranteed to work, all members will be set to 0[Ref 1].
The second is more readable.
The choice depends on user preference or the one which your coding standard mandates.
[Ref 1] Reference C99 Standard 6.7.8.21:
If there are...
Force R not to use exponential notation (e.g. e+10)?
Can I force R to use regular numbers instead of using the e+10 -like notation? I have:
4 Answers
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