Dan Saks wrote about this in 1995, during the lead up to C++ standardisation: The committees decided that functions such as this, that accept a pointer or reference to an array with unknown bound, complicate declaration matching and overload resolution rules in C++. The committees agreed that, since such functions have little utility and are … Read more
use [] with a string to pull out properties from objects dynamically. var a = { foo: 123 }; a.foo // 123 a[‘foo’] // 123 var str=”foo”; a[str] // 123 Which means we can refactor your method like so, just pass in the names of the properties you want to read as strings. var getKeyValueMap … Read more
The important thing to remember is that functions are first class objects in JavaScript. So you can pass them around as parameters, use them as object values and so on. Value(s) in an array are just one example of that. Note that we are not storing the functions in an array although we can do … Read more
Why defining a function within a function? To keep it isolated. It’s only used in this one place. Why define it more globally when it’s used locally?
You could also use boost for this task: #include <boost/math/special_functions/fpclassify.hpp> // isnan if( boost::math::isnan( … ) …. )
If I understand you correctly: changes context | n | y | accepts array n | func() | func.call() | of arguments y | ???????? | func.apply() | PHP has a function for this, call_user_func_array. Unfortunately, JavaScript is lacking in this regard. It looks like you simulate this behavior using eval(). Function.prototype.invoke = function(args) { … Read more
sort(my_list_of_objects, key=my_number_giving_function) same for sorted, see the Python Sorting HOWTO
Local functions in C# are clever in terms of their capturing – at least in the Roslyn implementation. When the compiler is able to guarantee that you aren’t creating a delegate from the local function (or doing something else that will prolong the lifetime of the variable) it can use a ref parameter with all … Read more
primes, in your code, is not a function, but a constant, in haskellspeak known as a CAF. If it took a parameter (say, ()), you would get two different versions of the same list back if calling it twice, but as it is a CAF, you get the exact same list back both times; As … Read more