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find() with nil when there are no records
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Yes, just do:
Challenge.find_by_id(10)
For Rails 4 and 5:
Challenge.find_by(id: 10)
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Is it more efficient to copy a vector by reserving and copying, or by creating and swapping? [duplic
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@rlbond Accidentally downvoted the answer :(, Can you please edit the post, so that i can remove the downvote and give the upvote?
– Shubham Sharma
Jul 24 at 17:32
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How to create a GUID/UUID using iOS
...tring = CFUUIDCreateString(NULL, theUUID);
CFRelease(theUUID);
return (__bridge NSString *)string;
}
EDIT: Jan, 29 2014:
If you're targeting iOS 6 or later, you can now use the much simpler method:
NSString *UUID = [[NSUUID UUID] UUIDString];
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Is it possible to decompile a compiled .pyc file into a .py file?
... .pyc bytecode into .py, whereas unpyclib crashed with an exception.
With all these tools, you get your code back including variable names, but without the comments.
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static linking only some libraries
How can I statically link only a some specific libraries to my binary when linking with GCC?
8 Answers
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How to remove stop words using nltk or python
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Note: this converts the sentence to a SET which removes all the duplicate words and therefore you will not be able to use frequency counting on the result
– David Dehghan
Feb 21 '17 at 23:59
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Entity Framework DateTime and UTC
...y Framework (I am using the Code First Approach with CTP5 currently) store all DateTime values as UTC in the database?
13 A...
How to find keys of a hash?
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There is function in modern JavaScript (ECMAScript 5) called Object.keys performing this operation:
var obj = { "a" : 1, "b" : 2, "c" : 3};
alert(Object.keys(obj)); // will output ["a", "b", "c"]
Compatibility details can be found here.
On the Mozilla site there is also a sn...
Why do you have to call .items() when iterating over a dictionary in Python?
...te over the same items. Implementation-wise they are different operations (__contains__ vs. __iter__). But that little inconsistency would be somewhat confusing and, well, inconsistent.
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Subprocess changing directory
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@The_Diver That's why cd must be implemented as internal shell command. There's no other way to do it. Internal shell commands are executed within the same process as the shell. What I meant by subshell is the shell executed for ...