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What are iterators and generators?
Iterators are used mostly to iterate or convert other objects to an iterator using iter() function. Generators are mostly used in loops to generate an iterator by returning all the values in the loop without affecting the iteration of the loop. Iterator uses iter() and next() functions.
What is the difference between iterator and iterable?
Iterable is an object, which one can iterate over. Iterator is an object, which is used to iterate over an iterable object using __next__() method. Iterators have __next__() method, which returns the next item of the object. Note that every iterator is also an iterable, but not every iterable is an iterator.
What is IterableIterator?
IterableIterator Interface, on the other hand is an interface defined by TypeScript that combines the contracts of Iterables and Iterator into one. This is because, in some cases, it makes sense to have the Iterable as an Iterator itself, removing the need to have an external class that serves as the iterator.
What are the types of iterator?
Types of Iterators :
- Input Iterators.
- Output Iterators.
- Forward Iterator.
- Bidirectional Iterators.
- Random-Access Iterators.
Which is better generator or iterator?
An iterator does not make use of local variables, all it needs is iterable to iterate on. A generator may have any number of ‘yield’ statements. You can implement your own iterator using a python class; a generator does not need a class in python. They are also simpler to code than do custom iterator.
Is Python list an iterator?
A list is an iterable. But it is not an iterator. If we run the __iter__() method on our list, it will return an iterator.
What are three main kinds of iterators?
2.2. 1.1 Kinds of Input Iterators. There are three main kinds of input iterators: ordinary pointers, container iterators, and input streams iterators.
How many iterator methods are there?
Methods of Iterator The Iterator interface provides 4 methods that can be used to perform various operations on elements of collections.
Is generator a iterator?
Every generator is an iterator, but not vice versa. A generator is built by calling a function that has one or more yield expressions ( yield statements, in Python 2.5 and earlier), and is an object that meets the previous paragraph’s definition of an iterator .
When to use an iterator in a list?
Typically it keeps a separate piece of information (such as the current index in the list) as well as referring to the collection itself. Although iterators are typically used for in-memory collections, they certainly don’t have to be, as we’ll see later. The key is the “ask for data, process it, ask for more data” cycle.
How are Iterator blocks different from other methods?
These features of iterator blocks make them completely different from other methods – it can be quite tricky to get your head round how they work, until it suddenly clicks. It can be quite useful to debug into an iterator block to really see how the flow works for yourself.
How are delegates used in iterator blocks in LINQ?
Flexibility is provided in LINQ to Objects by the use of delegates which can act on the input elements – for example, to act as a predicate in a filter, indicating whether or not a particular value should pass the filter; or as a projection to map one value to another.
How to iterate over the contents of an IEnumerator?
The basic idea is that as a data consumer, you can ask an IEnumerable for an IEnumerator with the GetEnumerator () call, and then iterate over the contents of the IEnumerator (using the MoveNext () method and Current property) until either you no longer need any more data, or the iterator runs out information to return.