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Why is it necessary to set the prototype constructor?
....create(Person.prototype);
Now what happens when we create a new Student and copy it?
var student1 = new Student("trinth");
console.log(student1.copy() instanceof Student); // => false
The copy is not an instance of Student. This is because (without explicit checks), we'd have no wa...
Database Design for Revisions?
...tribute. This just causes problems down the line, requires surrogate keys and all sorts of other problems.
Design 2 does have problems with schema changes. If you change the Employees table you have to change the EmployeeHistories table and all the related sprocs that go with it. Potentially doub...
How to install a gem or update RubyGems if it fails with a permissions error
... using gem install mygem or update RubyGems using gem update --system , and it fails with this error:
27 Answers
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How does a Java HashMap handle different objects with the same hash code?
As per my understanding I think:
14 Answers
14
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Volatile vs Static in Java
...t correct to say that static means one copy of the value for all objects and volatile means one copy of the value for all threads?
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Using jQuery to compare two arrays of Javascript objects
...that I'd like to compare to see if they are the same. The objects may not (and most likely will not) be in the same order in each array. Each array shouldn't have any more than 10 objects. I thought jQuery might have an elegant solution to this problem, but I wasn't able to find much online.
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How to use filter, map, and reduce in Python 3
filter , map , and reduce work perfectly in Python 2. Here is an example:
7 Answers
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Disable same origin policy in Chrome
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Close chrome (or chromium) and restart with the --disable-web-security argument. I just tested this and verified that I can access the contents of an iframe with src="http://google.com" embedded in a page served from "localhost" (tested under chromium ...
What is the purpose of .PHONY in a Makefile?
...e used to build files from other files. Make assumes its target is a file, and this makes writing Makefiles relatively easy:
foo: bar
create_one_from_the_other foo bar
However, sometimes you want your Makefile to run commands that do not represent physical files in the file system. Good example...
Declaring variables inside or outside of a loop
...that str absolutely ought to be declared within the while loop. No ifs, no ands, no buts.
The only case where this rule might be violated is if for some reason it is of vital importance that every clock cycle must be squeezed out of the code, in which case you might want to consider instantiating s...