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What is scope/named_scope in rails?
...a collection. Sounds complicated? It isn't. Imagine this:
You have Users. Now, some of those Users are subscribed to your newsletter. You marked those who receive a newsletter by adding a field to the Users Database (user.subscribed_to_newsletter = true). Naturally, you sometimes want to get those ...
What's the difference between window.location= and window.location.replace()?
...)
This code is perfectly correct syntax-wise, logic wise, type-wise
you know the only thing wrong with it?
it has location instead of location.href
what about this
var mystring = location = "#/some/spa/route"
what is the value of mystring? does anyone really know without doing some test. No ...
Replace multiple strings with multiple other strings
..."I have a cat, a dog, and a goat.";
str = str.replace(/cat/gi, "dog");
// now str = "I have a dog, a dog, and a goat."
str = str.replace(/dog/gi, "goat");
// now str = "I have a goat, a goat, and a goat."
str = str.replace(/goat/gi, "cat");
// now str = "I have a cat, a cat, and a cat."
...
List goals/targets in GNU make that contain variables in their definition
...vial makefile, dummy.mk, with these contents:
__all_targets__: ; #no-op
Now invoke make as make -p -f Makefile -f dummy.mk __all_targets__. On any substantial build, the difference in the amount of output generated by make is significant. For example:
$ gmake -pn | wc
138985 2632330 69612711
...
Can lambda functions be templated?
... the standard draft.
UPDATE 2014: C++14 has been released this year and now provides Polymorphic lambdas with the same syntax as in this example. Some major compilers already implement it.
At it stands (in C++11), sadly no. Polymorphic lambdas would be excellent in terms of flexibility and pow...
What does immutable mean?
...initial string?
Yes. Nothing can change the string once it is created. Now this doesn't mean that you can't assign a new string object to the str variable. You just can't change the current object that str references.
If the string was mutable, does that
mean the 2nd alert() would return ...
What are the implications of using “!important” in CSS? [duplicate]
...
}
button.highlight {
color: blue;
font-size: 1.5em;
}
button#buyNow {
color: green;
font-size: 2em;
}
On this page, all buttons are black. Except the buttons with the class "highlight", which are blue. Except that one unique button with the ID "buyNow", which is green. The impo...
How to get the name of enumeration value in Swift?
...
As of Xcode 7 beta 5 (Swift version 2) you can now print type names and enum cases by default using print(_:), or convert to String using String's init(_:) initializer or string interpolation syntax. So for your example:
enum City: Int {
case Melbourne = 1, Chelyabin...
How do I check if an element is really visible with JavaScript? [duplicate]
...
I don't know how much of this is supported in older or not-so-modern browsers, but I'm using something like this (without the neeed for any libraries):
function visible(element) {
if (element.offsetWidth === 0 || element.offsetHeig...
Command copy exited with code 4 when building - Visual Studio restart solves it
Every now and then when I build my solution here (with 7 projects in it) I get the dreaded 'Command copy exited with code 4' error, in Visual Studio 2010 Premium ed.
...