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Why is null an object and what's the difference between null and undefined?
...nown what the value is.
One thing to remember is that null is not, conceptually, the same as false or "" or such, even if they equate after type casting, i.e.
name = false;
You: What is name?
JavaScript: Boolean false.
name = '';
You: What is name?
JavaScript: Empty string
*: name in this context...
What is Type-safe?
...m:
int AddTwoNumbers(int a, int b)
{
return a + b;
}
If I tried to call that using:
int Sum = AddTwoNumbers(5, "5");
The compiler would throw an error, because I am passing a string ("5"), and it is expecting an integer.
In a loosely typed language, such as javascript, I can do the follow...
What does enumerable mean?
...his condition is in place because objects have many more properties, especially from inheritance:
console.log(Object.getOwnPropertyNames(Object.prototype));
// ["constructor", "toString", "toLocaleString", "valueOf", "hasOwnProperty", "isPrototypeOf", "propertyIsEnumerable", /* etc. */]
Each of t...
JavaScript Nested function
...ion in the same way it would change the scope of a variable. This is especially important for use with closures to reduce total global namespace pollution.
The functions defined within another function won't be accessible outside the function unless they have been attached to an object that is acce...
Curious null-coalescing operator custom implicit conversion behaviour
...l; there's no need to check it for null a second time just because we are calling a lifted conversion operator". We'd them optimize it away to just
new int?(op_Implicit(temp2.Value))
My guess is that we are somewhere caching the fact that the optimized form of (int?)Foo() is new int?(op_implici...
What is the meaning of the 'g' flag in regular expressions?
...
g is for global search. Meaning it'll match all occurrences. You'll usually also see i which means ignore case.
Reference: global - JavaScript | MDN
The "g" flag indicates that the regular expression should be tested against all possible matches in a string.
Wit...
Can I change a private readonly field in C# using reflection?
...mplementation today does not mean that you can on every implementation for all time. I am not aware of any place where we document that readonly fields must be mutable via reflection. As far as I know, a conforming implementation of the CLI is perfectly free to implement readonly fields such that th...
throw Error('msg') vs throw new Error('msg')
...this is explicitly stated in the specification:
... Thus the function call Error(…) is equivalent to the object creation expression new Error(…) with the same arguments.
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Catching an exception while using a Python 'with' statement
... print 'oops'
If you want different handling for errors from the open call vs the working code you could do:
try:
f = open('foo.txt')
except IOError:
print('error')
else:
with f:
print f.readlines()
...
AngularJS - How to use $routeParams in generating the templateUrl?
...his issue too - the solution is to do something like $routeProvider.when("/foo", { controller : "FooController", controllerAs : "foo", templateUrl: "foo.html" });
– Erin Drummond
Sep 24 '14 at 22:36
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