Python 2.6+ and Python 3: If you want StopIteration to be raised if no matching element is found: next(x for x in the_iterable if x > 3) If you want default_value (e.g. None) to be returned instead: next((x for x in the_iterable if x > 3), default_value) Note that you need an extra pair of … Read more
I would prefer it – vec.begin() precisely for the opposite reason given by Naveen: so it wouldn’t compile if you change the vector into a list. If you do this during every iteration, you could easily end up turning an O(n) algorithm into an O(n^2) algorithm. Another option, if you don’t jump around in the … Read more
Iteration is a general term for taking each item of something, one after another. Any time you use a loop, explicit or implicit, to go over a group of items, that is iteration. In Python, iterable and iterator have specific meanings. An iterable is an object that has an __iter__ method which returns an iterator, … Read more
One way is to create a Spliterator from the Iterator and use that as a basis for your stream: Iterator<String> sourceIterator = Arrays.asList(“A”, “B”, “C”).iterator(); Stream<String> targetStream = StreamSupport.stream( Spliterators.spliteratorUnknownSize(sourceIterator, Spliterator.ORDERED), false); An alternative which is maybe more readable is to use an Iterable – and creating an Iterable from an Iterator is very easy … Read more
C++03 (Source: Iterator Invalidation Rules (C++03)) Insertion Sequence containers vector: all iterators and references before the point of insertion are unaffected, unless the new container size is greater than the previous capacity (in which case all iterators and references are invalidated) [23.2.4.3/1] deque: all iterators and references are invalidated, unless the inserted member is at … Read more
tl;dr In ECMAScript 2017, just call Object.entries(yourObj). In ECMAScript 2015, it is possible with Maps. In ECMAScript 5, it is not possible. ECMAScript 2017 ECMAScript 2017 introduced a new Object.entries function. You can use this to iterate the object as you wanted. ‘use strict’; const object = {‘a’: 1, ‘b’: 2, ‘c’ : 3}; for … Read more
Iterator objects in python conform to the iterator protocol, which basically means they provide two methods: __iter__() and __next__(). The __iter__ returns the iterator object and is implicitly called at the start of loops. The __next__() method returns the next value and is implicitly called at each loop increment. This method raises a StopIteration exception … Read more
To safely remove from a collection while iterating over it you should use an Iterator. For example: List<String> names = …. Iterator<String> i = names.iterator(); while (i.hasNext()) { String s = i.next(); // must be called before you can call i.remove() // Do something i.remove(); } From the Java Documentation : The iterators returned by … Read more
iterator is a more general concept: any object whose class has a __next__ method (next in Python 2) and an __iter__ method that does return self. 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 … Read more
Python 3.6 version of the above answer, using os – assuming that you have the directory path as a str object in a variable called directory_in_str: import os directory = os.fsencode(directory_in_str) for file in os.listdir(directory): filename = os.fsdecode(file) if filename.endswith(“.asm”) or filename.endswith(“.py”): # print(os.path.join(directory, filename)) continue else: continue Or recursively, using pathlib: from pathlib import … Read more