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What is the advantage of using forwarding references in range-based for loops?
...or<bool> v(10);
for (auto&& e : v)
e = true;
}
All that being said, I wouldn't code this way unless you knew you needed to satisfy such a use case. I.e. I wouldn't do this gratuitously because it does cause people to wonder what you're up to. And if I did do it, it woul...
Using python's eval() vs. ast.literal_eval()?
...
datamap = eval(raw_input('Provide some data here: ')) means that you actually evaluate the code before you deem it to be unsafe or not. It evaluates the code as soon as the function is called. See also the dangers of eval.
ast.literal_eval raises an exception if the input isn't a valid Python dat...
Unable to create a constant value of type Only primitive types or enumeration types are supported in
...I'm concerned about performance I should avoid doing this as it would load all data in memory first and then query it. Should I write raw sql for this scenarios?
– Arvand
Dec 28 '15 at 11:30
...
Ruby on Rails: How can I revert a migration with rake db:migrate?
...ake db:migrate VERSION=<version number>
– Ajedi32
Jun 3 '13 at 19:06
3
At least for rails 3...
How does a public key verify a signature?
... add a digital signature to a document using his/her private key to essentially obtain a hash of the document, but what I do not understand is how the public key can be used to verify that signature.
...
MySQL ON vs USING?
... far as I can tell, USING() is just more convenient syntax, whereas ON allows a little more flexibility when the column names are not identical. However, that difference is so minor, you'd think they'd just do away with USING() .
...
CMake: Print out all accessible variables in a script
I'm wondering if there is a way to print out all accessible variables in CMake. I'm not interested in the CMake variables - as in the --help-variables option. I'm talking about my variables that I defined, or the variables defined by included scripts.
...
Sqlite primary key on multiple columns
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@pratnala In standard SQL, yes. In SQLite, NULL is allowed in primary keys. This answer emphasizes that if you want more standard behavior, you need to add the NOT NULL yourself. My answer is just the very basic syntax for a multi-column primary key.
– B...
val() vs. text() for textarea
...
Yoav Kadosh
3,23544 gold badges2323 silver badges5252 bronze badges
answered Apr 10 '14 at 16:50
Kshitij Saxena -KJ-Kshitij Saxena -K...
Create a new object from type parameter in generic class
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Because the compiled JavaScript has all the type information erased, you can't use T to new up an object.
You can do this in a non-generic way by passing the type into the constructor.
class TestOne {
hi() {
alert('Hi');
}
}
class TestTwo {
...