mutable

Not sure if this is a style question, or something that has a hard rule... If I want to keep the public method interface as const as possible, but make the object thread safe, should I use mutable mutexes? In general, is this good style, or should a non-const method interface be preferred? Please justify your view. [ Answer edited ] Basically using const methods with mutable mutexes is a good idea (don't return references by the way, make sure to return by value), at least to indicate they do not modify the object. Mutexes should not be const, it would be a shameless lie to define lock/unlock

This question already has an answer here: Are strings mutable in Ruby? 2 answers Consider the following code: $ irb > s = "asd" > s.object_id # prints 2171223360 > s[0] = ?z # s is now "zsd" > s.object_id # prints 2171223360 (same as before) > s += "hello" # s is now "zsdhello" > s.object_id # prints 2171224560 (now it's different) Seems like individual characters can be changed w/o creating a new string. However appending to the string apparently creates a new string. Are strings in Ruby mutable? Yes, strings in Ruby, unlike in Python, are mutable. s += "hello" is not appending "hello" to s -

I am writing an Array-derived class in JavaScript and need to know which functions to overload so that I can be aware of changes made to the array. I know Array.push() and Array.splice() are mutating. Is there a definitive list of any others? Jonathan Lonowski You can find the list on MDN as Mutator methods (along with Accessor and Iteration methods): copyWithin fill pop push reverse shift sort splice unshift You can also use .concat() , before using your mutation method, to ensure you are not mutating your arrays, eg const dontMutateMe = [4,5,1,2,3]; const sortArray = dontMutateMe.concat()

As per my knowledge, a mutable string can be changed, and an immutable string cannot be changed. Here I want to change the value of String like this, String str="Good"; str=str+" Morning"; and other way is, StringBuffer str= new StringBuffer("Good"); str.append(" Morning"); In both the cases I am trying to alter the value of str . Can anyone tell me, what is difference in both case and give me clear picture of mutable and immutable objects. TheLostMind Case 1: String str = "Good"; str = str + " Morning"; In the above code you create 3 String Objects. "Good" it goes into the String Pool . "