Even languages where you have explicit pointer manipulation like C it's always passed by value (you can pass them by reference but that's not the default behavior).
What is the benefit of this, why are so many languages passed by values and why are others passed by reference ? (I understand Haskell is passed by reference though I'm not sure).
Best Answer
Pass by value is often safer than pass by reference, because you cannot accidentally modify the parameters to your method/function. This makes the language simpler to use, since you don't have to worry about the variables you give to a function. You know they won't be changed, and this is often what you expect.
However, if you want to modify the parameters, you need to have some explicit operation to make this clear (pass in a pointer). This will force all your callers to make the call slightly differently (
&variable, in C) and this makes it explicit that the variable parameter may be changed.So now you can assume that a function will not change your variable parameter, unless it is explicitly marked to do so (by requiring you to pass in a pointer). This is a safer and cleaner solution than the alternative: Assume everything can change your parameters, unless they specifically say they can't.