type-coercion

In trying to answer How to instantiate Moose classes from a big hash , I think I have hit another place where I don't fully understand Moose type coercions. For some reason, the below code issues warnings: You cannot coerce an attribute (departments) unless its type (ArrayRef[Company::Department]) has a coercion at ./test.pl line 12. You cannot coerce an attribute (employees) unless its type (ArrayRef[Company::Person]) has a coercion at ./test.pl line 23. but then succeeds. #!/usr/bin/env perl use warnings; use strict; package Company; use Moose; use Moose::Util::TypeConstraints; has 'id' =>

data: function( elem, name, data ) { if ( !jQuery.acceptData( elem ) ) { return; } elem = elem == window ? windowData : elem; Copied directly from the jQuery source. Why is it not safe to use elem === window ? Why does jQuery use type coercion on the window object? It would appear that in IE there's an issue with top top == window // true top === window // false Raynos See here for why checking againts the window object with === is unsafe in IE. I think the root cause is that IE is closely coupled with the Windows OS so you have various OS objects referenced through window and the equality

Given that a literal number not strictly an instance of Number, why can I call prototype methods of Number (or String, or Boolean) objects on the corresponding literal objects? Is this standard behavior across browsers? What exactly is happening when this occurs? I suspect it's coercing the literal into the corresponding type before calling the method, because when I inspect typeof this in the method, it's returning 'object' rather than 'number'. The literal is not coerced into an instance. What happens internally, is that an instance is created, the value is copied to the instance and the

I've been reading about JavaScript hoisting sometime back. JavaScript Scoping and Hoisting by Ben Cherry Two words about “hoisting” by Dmitry Soshnikov and, some more about JavaScript type-coercion, truth & false test: Truth, Equality and JavaScript and some other resource And while practicing some, and found I m missing some important concept about the hoisting and a variable' truthy & falsy. 1: 'if' truth test with duplicate variable declaration var foo = 1; function bar() { if (!foo) { alert('inside if'); var foo = 10; } } bar(); o/p: inside if Doubt: 'foo' value being '1', if(!foo) should

I'm comparing strings with comparison operators. I needs some short of explanations for the below two comparisons and their result. if('ai' > 'i') { echo 'Yes'; } else { echo 'No'; } output: No Why do these output this way? if('ia' > 'i') { echo 'Yes'; } else { echo 'No'; } Output: Yes Again, why? Maybe I forgot some basics, but I really need some explanation of these comparison examples to understand this output. coderabbi PHP will compare alpha strings using the greater than and less than comparison operators based upon alphabetical order. In the first example, ai comes before i in

I am trying to achieve the functionality similar to unlist, with the exception that types are not coerced to a vector, but the list with preserved types is returned instead. For instance: flatten(list(NA, list("TRUE", list(FALSE), 0L)) should return list(NA, "TRUE", FALSE, 0L) instead of c(NA, "TRUE", "FALSE", "0") which would be returned by unlist(list(list(NA, list("TRUE", list(FALSE), 0L)) . As it is seen from the example above, the flattening should be recursive. Is there a function in standard R library which achieves this, or at least some other function which can be used to easily and