Mutable strings in Python
In Python mutable sequence type is bytearray see this link
mutable
What is difference between mutable and immutable String in java
Case 1: String str = “Good”; str = str + ” Morning”; In the above code you create 3 String Objects. “Good” it goes into the String Pool. ” Morning” it goes into the String Pool as well. “Good Morning” created by concatenating “Good” and ” Morning”. This guy goes on the Heap. Note: Strings … Read more
Which JavaScript Array functions are mutating?
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
In Kotlin, how do you modify the contents of a list while iterating
First, not all copying of a list is bad. Sometimes a copy can take advantage of CPU cache and be extremely fast, it depends on the list, size, and other factors. Second, for modifying a list “in-place” you need to use a type of list that is mutable. In your sample you use listOf which … Read more
Are mutable hashmap keys a dangerous practice?
It has been noted by many well respected developers such as Brian Goetz and Josh Bloch that : If an object’s hashCode() value can change based on its state, then we must be careful when using such objects as keys in hash-based collections to ensure that we don’t allow their state to change when they … Read more
Should mutexes be mutable?
The hidden question is: where do you put the mutex protecting your class? As a summary, let’s say you want to read the content of an object which is protected by a mutex. The “read” method should be semantically “const” because it does not change the object itself. But to read the value, you need … Read more
Converting mutable to immutable map
The immutable hierarchy doesn’t contain a MultiMap, so you won’t be able to use the converted structure with the same convenient syntax. But if you’re happy to deal with key/valueset pairs, then: If you just want a mutable HashMap, you can just use x.toMap in 2.8 or collection.immutable.Map(x.toList: _*) in 2.7. But if you want … Read more
Mutable variable is accessible from closure. How can I fix this?
I liked the paragraph Closures Inside Loops from Javascript Garden It explains three ways of doing it. The wrong way of using a closure inside a loop for(var i = 0; i < 10; i++) { setTimeout(function() { console.log(i); }, 1000); } Solution 1 with anonymous wrapper for(var i = 0; i < 10; i++) … Read more
What is the syntax for adding an element to a scala.collection.mutable.Map?
The point is that the first line of your code is not what you expected. You should use: val map = scala.collection.mutable.Map[A,B]() You then have multiple equivalent alternatives to add items: scala> val map = scala.collection.mutable.Map[String,String]() map: scala.collection.mutable.Map[String,String] = Map() scala> map(“k1”) = “v1” scala> map res1: scala.collection.mutable.Map[String,String] = Map((k1,v1)) scala> map += “k2” -> … Read more
Immutable/Mutable Collections in Swift
Arrays Create immutable array First way: let array = NSArray(array: [“First”,”Second”,”Third”]) Second way: let array = [“First”,”Second”,”Third”] Create mutable array var array = [“First”,”Second”,”Third”] Append object to array array.append(“Forth”) Dictionaries Create immutable dictionary let dictionary = [“Item 1”: “description”, “Item 2”: “description”] Create mutable dictionary var dictionary = [“Item 1”: “description”, “Item 2”: “description”] Append … Read more