It is highly suspicious when a value is saved for a key or index and then unconditionally overwritten. Such replacements are likely in error.

Noncompliant Code Example

 fruits[1] = "banana";
 fruits[1] = "apple";  // Noncompliant - value on index 1 is overwritten

 myMap.set("key", 1);
 myMap.set("key", 2); // Noncompliant - value for key "key" is replaced

 mySet.add(1);
 mySet.add(1); // Noncompliant - element is already in the set