An iterator is an object-oriented programming pattern which for the most part functions similarly to a pointer to an object inside a collection with the added ability to traverse through the collection in a defined manner, agnostic of the actual implementation or even object addresses in physical ...

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Thread-safe Iterator wrapper

Aside: This code assumes a class Option that can be Some or None to represent the presence (Some) or absence (None) of the value it contains. Haskell calls it Maybe. Here is my first pass at ...
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0answers
31 views

Array slice type in Java - follow-up

See the previous iteration. I have essentially fixed most of the issues mentioned by maaartinus. However, I left the size field as it is. Namely, if the user wants ...
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1answer
41 views

Array slice type in Java

Edit See the next iteration at Array slice type in Java - follow-up. I have this "slice" type for managing array subranges. It is kind of the same thing as Pythons slice notation, yet I did not add ...
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2answers
139 views

Streaming int support

This recent question Print Consecutive numbers by comparing two parameters frustrated me because I could not find a convenient way in Java 8 to support the conditions that are required. I answered it ...
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2answers
63 views

Iterator to remove duplicate element

The code implements custom iterator, which skips duplicate integers. The array expected is to be sorted. ...
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0answers
49 views

Functional tree iteration in Common Lisp

I'm adding some functionality to an existing library of data structures in Common Lisp, with a view to asking the original author if I can take over maintenance and development of it. While the ...
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1answer
81 views

Modern C++ compliant insertion sort

This is a kind of follow up to my previous sort implementation question with specific questions to insertion sort, and Modern C++ idioms. Anybody seeing this post can see how I got to this modern ...
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2answers
151 views

Doubly linked list: iterator/pointer arithmetic

I'm using a doubly linked list container I've written as the working example. The textbook I'm using is from 2001, so feel free to point out where later versions of the C++ standard should be used ...
3
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1answer
41 views

AdjacentElementsIteratorAdaptor for Random Access Iterators

Inspired by this comment I decided to implement an iterator adaptor that takes another iterator and returns each element and a given number of its neighbors. The final solution should be applicable ...
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2answers
65 views

Iterating over the lines of a stream

This structure is supposed to iterate over the lines of an input stream, using std::getline. Any remark is welcome! ...
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2answers
139 views

Lazy String.Split

C#'s String.Split method comes from C# 2.0, and lazy operations weren't a feature back then. The task is to split a string according to a (single) separator. Doing ...
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0answers
28 views

A context-based partition_copy

I recently posted a question on Stack Overflow asking how I could go about implementing a context-based partition copy. I actually came up with my own solution, but I would like to see if it could be ...
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0answers
31 views

Adaptive cyclic database iterator

This is a bit tricky to explain. I'm trying to model a cyclic iterator that would return the next available DataSource(SQL). So infinite calls would just pick the ...
2
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1answer
109 views

Iterator requirements for a fake container supporting C++11 range-based for

Around a year ago, I wrote this Stack Overflow answer where I suggested an idea to replace deeply nested loops with a single iterable virtual-container object that "contains" all the indices. The ...
3
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1answer
69 views

Wrapping WinAPI FindNextVolume as std iterator

This is my first attempt at creating an STL-style iterator. Is this code ok? ...
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2answers
96 views

Two permutation iterators for classes in Python with and without a generator

I am just testing out a couple of small classes for learning purposes. Here is my current working code: ...
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3answers
124 views

Functions taking iterables: peaks, compress, and skipper

I am just testing out a few small functions for learning purposes: ...
7
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1answer
79 views

Serialization: Escape Input String

In Json strings characters can be escaped with \\. Here is an iterator that can read such strings and convert the escaped characters to UTF-8 ...
2
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2answers
163 views

Bag data structure (a set that can store multiple copies of items)

I am trying to make my class a bit cleaner, especially some of its methods like Count, __add__, ...
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2answers
236 views

Interleaving values from several iterables

I am new to Python and am trying to see if there is a cleaner way to write my code. The following code take iterables as parameter it produces the first value from the first parameter, then the first ...
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votes
2answers
231 views

Sorting function that also works with containers having only forward iterators

I was playing around with some code trying to implement a sorting algorithm in C++ that also works with singly linked lists. Since the merge routine of mergesort only scans forward, implementing a ...
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0answers
51 views

Reversing the “words” of a container with a bidirectional iterator

I posted another snippet of code a few weeks back when I started learning C++. Here's my second try now that I have some time to play with this again. The goal is to write a generic algorithm for ...
3
votes
2answers
652 views

Custom iterator for a linked list class

I have made a LinkedList class. This is a singly-linked-list and I want to make a forward_iterator for this class without using ...
4
votes
1answer
103 views

Sieve prime generator C++

I had some issues with the behavior of the iterator in my prime generator: ...
3
votes
3answers
191 views

Iteritems on a slice of a Python list

iteritems on a dict can useful. Occasionally iteritems is useful for a slice of a list and ...
3
votes
1answer
556 views

StreamIterable - create an iterable from a Java 8 Stream

This seems like an easy thing to mess up, so I'd be grateful if you could think of any edge-cases that I've missed. ...
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1answer
47 views

Homogenising iterator and const_iterator

I've reworked (for C++11) a section of PyCXX which contained an almost identical iterator and const_iterator. I would like to ...
2
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1answer
197 views

ArrayList for Shop implementatin

Problem statement: Design a system for the following scenario: An item list contains item code, name, rate, and quantity for several items. Whenever a new item is added in the list ...
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2answers
86 views

Handling thread interruptions in a directory iterator

This code is code written on a whim to help $someindividual asking for such a thing on $somechatmedium; what is needed is a way, ...
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2answers
203 views

Elementwise iterator adaptor

There are many C++ implementations of the Euclidean vector. I.e., a vector in what is typically a 3- or 4-dimensional space. Something along the lines of ...
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3answers
237 views

Cyclic iterator in both directions

I am trying to make a cyclic iterator that works backwards and forwards. getNext() gets the next array item, getPrevious() gets ...
8
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2answers
222 views

Self-made linked list iterator

I recently made a linked list for myself, the code of which was posted here, if anyone would be interested. Now, as the next task, I had to make an Iterator for my ...
4
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1answer
33 views

Finding the next XML element

I am looking for a better way to do a while cycle with the variable update. The background is that I'm writing a StAX-line XML reader in JavaScript and want to ...
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2answers
156 views

Array-like container for uints shorter than 8 bits (Rev 1)

This is a follow-up to Array-like container for uints shorter than 8 bits In short: The PackedBitfieldArray should be a kind of container for packed (unsigned) ...
11
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1answer
147 views

Array-like container for uints shorter than 8 bits

Follow-up: Array-like container for uints shorter than 8 bits (Rev 1) First of all: yes, I need this kind of array to generate data for a piece of hardware, and it must be stored and manipulated ...
7
votes
2answers
413 views

Sorted vector (aka flat_set) for objects (pointers) with custom embedded key (functor used)

BEFORE YOU READ: this link should be included when you just don't like the format of the question and for those that read this question for the first time, the link may give you the idea what happened ...
4
votes
2answers
75 views

Custom MultiIterator with type filter

I'll start with giving a bit of background as there are many classes involved and I can't attach all of them because that would make this question wildly too long. For the curios they can be found at ...
3
votes
1answer
146 views

Return one particular element first, when iterating a lua table

I wish to iterate through a Lua table, but want to get one particular element first always (its key is known beforehand). Since the pairs function does not guarantee the order of a table's elements, ...
4
votes
1answer
129 views

Python caching generator

Is this the correct way to cache a generator in Python, without iterating over it right away (for example using list() over it)? ...
15
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1answer
248 views

CircularListCursor - an efficient circular cursor on any list

I have decided to create my own CircularListCursor, because I wanted some abstraction and a ListIterator<E> couldn't give ...
2
votes
1answer
105 views

Graceful way to iterate through two arrays and build a master array?

params[:controller_id].each do |cid| params[:zone_number].each do |pzn| zone_ids << Zone.find_by_controller_id_and_number(cid,pzn).id end end I have ...
11
votes
1answer
423 views

Custom iterator implementation returning OpenCV Mat

I have written an adapter class that allows iteration over the rows of a Mat object from OpenCV. For those interested, here is the Mat documentation, but the ...
6
votes
3answers
225 views

Iterator of iterator

Given an iterator of iterators, return all of the elements from the iterators in order. Looking for code review, optimizations, and best practices. Verifying complexity to be \$O(n)\$, where \$n\$ is ...
5
votes
3answers
223 views

Iterator for a list of objects

Given a list of objects, return an iterator for such a list. Looking for code-review, optimizations and best practices. Verifying complexity to be O(n) where n is sum of all objects, including ...
5
votes
3answers
1k views

Linked list with iterators

This is my second linked list implementation for review. I rewritten pretty much all of this and have added iterators, sentinels and The Rule of Five. Please let me know what's wrong with it; I am ...
4
votes
1answer
109 views

Container which iterates a range or a list

I have made some composited container Range which accepts either a min/max range as a std::pair or a set of integers as a ...
4
votes
2answers
152 views

Recursive flatten with lazy evaluation iterator

I'm trying to rewrite this: ...
4
votes
5answers
564 views

A deduplicating iterator

Implement an iterator(Generic) which skips an element if it is equal to the previous element. e.g : AAABBCCCCD, produces ABCD. Below is my attempt. Please suggest improvements. ...
12
votes
3answers
12k views

Simple Example of an Iterable and an Iterator in Java

I was a TA for a first-year Java programming course this year. As a very simple example of iterables/iterators, I wrote the following code for the students. I am curious if any styling or other ...
10
votes
2answers
883 views

Using a Pythonesque range() generator function with the Java foreach loop

Now that we have the nice new foreach loop in Java, the old-style loop looks ugly be comparison. I like the way Python has a ...