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Pointers, smart pointers or shared pointers? [duplicate]
...ting/copying/destructing a shared pointer needs to be an atomic operation, and this can hinder performance if you have many threads running. However, it won't always be the case - only testing will tell you for sure.
There is an argument (that I like) against shared pointers - by using them, you ar...
ActiveRecord: size vs count
In Rails, you can find the number of records using both Model.size and Model.count . If you're dealing with more complex queries is there any advantage to using one method over the other? How are they different?
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How do I list the functions defined in my shell?
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declare -F
Function names and definitions may be listed with the -f option to the
declare builtin command (see Bash Builtins). The -F option to declare
will list the function names only
(and optionally the source file and line number).
Bash Re...
Converting from a string to boolean in Python?
...ref.html#distutils.util.strtobool
True values are y, yes, t, true, on and 1; false values are n, no, f, false, off and 0. Raises ValueError if val is anything else.
Be aware that distutils.util.strtobool() returns integer representations and thus it needs to be wrapped with bool() to get Bool...
How to check if object has any properties in JavaScript?
...ws:
for(var prop in ad) {
if (ad.hasOwnProperty(prop)) {
// handle prop as required
}
}
It is important to use the hasOwnProperty() method, to determine whether the object has the specified property as a direct property, and not inherited from the object's prototype chain.
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What is the difference between a static and a non-static initialization code block
...static from the initializer block, it then becomes an instance initializer and so int a is initialized at construction.
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ASP.Net error: “The type 'foo' exists in both ”temp1.dll“ and ”temp2.dll"
When running a web application project, at seemingly random times a page may fail with a CS0433 error: type exists in multiple DLL's. The DLL's are all generated DLL's residing in the "Temporary ASP.NET Files" directory.
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Size of character ('a') in C/C++
What is the size of character in C and C++ ? As far as I know the size of char is 1 byte in both C and C++.
4 Answers
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What, exactly, is needed for “margin: 0 auto;” to work?
...lement is used to centre it (left-right). However, I know that the element and its parent must meet certain criteria for the auto margin to work, and I can never seem to get the magic right.
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PDO mysql: How to know if insert was successful
I'm using PDO to insert a record (mysql and php)
7 Answers
7
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