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How do I use grep to search the current directory for all files having the a string “hello” yet disp
How do I use grep to search the current directory for any and all files containing the string "hello" and display only .h and .cc files?
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Visually managing MongoDB documents and collections [closed]
I'm using MongoDB in a reporting system and have to delete a whole bunch of test documents. While I don't have too much trouble using the JSON-based command-line tools, it gets extremely tedious to have to keep searching for documents, copy-and-pasting OIDs, etc., especially from a command prompt...
How to calculate the CPU usage of a process by PID in Linux from C?
I want to programmatically [in C] calculate CPU usage % for a given process ID in Linux.
12 Answers
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How to print number with commas as thousands separators?
...ying to print an integer in Python 2.6.1 with commas as thousands separators. For example, I want to show the number 1234567 as 1,234,567 . How would I go about doing this? I have seen many examples on Google, but I am looking for the simplest practical way.
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How can one print a size_t variable portably using the printf family?
... variable of type size_t , and I want to print it using printf() . What format specifier do I use to print it portably?
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Hide Utility Class Constructor : Utility classes should not have a public or default constructor
...ility class, you should make the class final and define a private constructor:
public final class FilePathHelper {
private FilePathHelper() {
//not called
}
}
This prevents the default parameter-less constructor from being used elsewhere in your code. Additionally, you can make the c...
Splitting a Java String by the pipe symbol using split(“|”)
...uses regular expression and in regex | is a metacharacter representing the OR operator. You need to escape that character using \ (written in String as "\\" since \ is also a metacharacter in String literals and require another \ to escape it).
You can also use
test.split(Pattern.quote("|"));
a...
What is an “unwrapped value” in Swift?
I'm learning Swift for iOS 8 / OSX 10.10 by following this tutorial , and the term " unwrapped value " is used several times, as in this paragraph (under Objects and Class ):
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How do I check if an object has a specific property in JavaScript?
...ed by the answers that have been given - most of them are just outright incorrect. Of course you can have object properties that have undefined, null, or false values. So simply reducing the property check to typeof this[property] or, even worse, x.key will give you completely misleading results.
I...
Undo scaffolding in Rails
...eady run the migrations generated by the scaffold command, you have to perform a rollback first.
rake db:rollback
You can create scaffolding using:
rails generate scaffold MyFoo
(or similar), and you can destroy/undo it using
rails destroy scaffold MyFoo
That will delete all the files cre...