String s = “”; String s2 = someUserInputVariale.toLowercase(); // where the user entered in “” Something like that would cause s == s2 to evaluate to false. Lots of code sill create new Strings without exposing the call to new String().
Although Microsoft’s Framework classes are unfortunately a bit inconsistent with regard to what Object.Equals(Object) means, in general X.Equals(Y) will only be true if replacing arbitrary references to X with references to Y, and/or vice versa, would not be expected to alter the semantics of the objects in question. For example, if X is a String … Read more
Because the definition of “equals” for Arrays is that they refer to the same array. This is consistent with Java’s array equality, using Object.Equals, so it compares references. If you want to check pairwise elements, then use sameElements Array(‘a’,’b’).sameElements(Array(‘a’,’b’)) or deepEquals, which has been deprecated in 2.8, so instead use: Array(‘a’,’b’).deep.equals(Array(‘a’,’b’).deep) There’s a good Nabble … Read more
As has been shown comparing two floats (or doubles etc) can be problematic. Generally, instead of comparing for exact equality they should be checked against an error bound. If they are within the error bound, they are considered equal. That is much easier said than done. The nature of floating point make a fixed error … Read more
Enumerable.SequenceEqual<TSource> MSDN
I agree that the equal function on the vector prototype is the best solution. Note that you can also build other infix-like operators via chaining. function Vector(x, y, z) { this.x = x; this.y = y; this.z = z; } Vector.prototype.add = function (v2) { var v = new Vector(this.x + v2.x, this.y + v2.y, … Read more
is verifies object identity, and any implementation of Python, when it meets literal of immutable types, is perfectly free to either make a new object of that immutable type, or seek through existing objects of that type to see if some of them could be reused (by adding a new reference to the same underlying … Read more
Use the getTime() method. It will check the numeric value of the date and it will work for both the greater than/less than checks as well as the equals checks. EDIT: if (d1.getTime() === d2.getTime())
You use == or === : var thesame = obj1===obj2; From the MDN : If both operands are objects, then JavaScript compares internal references which are equal when operands refer to the same object in memory.
The String#equals() not only compares the String’s contents, but also checks if the other object is also an instance of a String. The String#contentEquals() only compares the contents (the character sequence) and does not check if the other object is also an instance of String. It can be anything as long as it is an … Read more