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What is the difference between NULL, '\0' and 0?
...e appear to be differences between various values of zero -- NULL , NUL and 0 .
11 Answers
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Ruby: Easiest Way to Filter Hash Keys?
...t { |key, value| key.to_s.match(/^choice\d+/) }
or you can use delete_if and modify the existing Hash e.g.
params.delete_if { |key, value| !key.to_s.match(/choice\d+/) }
or if it is just the keys and not the values you want then you can do:
params.keys.select { |key| key.to_s.match(/^choice\d+...
Check if string contains only whitespace
...method:
Return True if there are only whitespace characters in the string and there is at least one character, False otherwise.
A character is whitespace if in the Unicode character database (see unicodedata), either its general category is Zs (“Separator, space”), or its bidirectional class is...
Hashing a dictionary?
...dictionary is not nested, you could make a frozenset with the dict's items and use hash():
hash(frozenset(my_dict.items()))
This is much less computationally intensive than generating the JSON string or representation of the dictionary.
UPDATE: Please see the comments below, why this approach mi...
Is it good style to explicitly return in Ruby?
...g my own style guidelines but I'm thinking about releasing my source code, and I'd like it to adhere to any unwritten rules that might exist.
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python pandas: apply a function with arguments to a series
I want to apply a function with arguments to a series in python pandas:
4 Answers
4
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How to test valid UUID/GUID?
...e is the NIL UUID, noted here. The following regex takes this into account and will return a match for a NIL UUID. See below for a UUID which only accepts non-NIL UUIDs. Both of these solutions are for versions 1 to 5 (see the first character of the third block).
Therefore to validate a UUID...
/^...
Detect rotation of Android phone in the browser with JavaScript
I know that in Safari on an iPhone you can detect the screen's orientation and change of orientation by listening for the onorientationchange event and querying window.orientation for the angle.
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java.lang.NoClassDefFoundError: Could not initialize class XXX
... properties from file
}
It would appear some uncaught exception occurred and propagated up to the actual ClassLoader attempting to load the class. We would need a stacktrace to confirm this though.
Either that or it occurred when creating PropHolder.prop static variable.
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Rails update_attributes without save?
...utes({ :name => 'Josh', :is_admin => true }) raises an error message and doesn't actually set the user's name property.
– Ajedi32
Sep 5 '12 at 19:50
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