This is Understanding Combine, written by Matt Neuburg. Corrections and suggestions are greatly appreciated (you can comment here). So are donations; please consider keeping me going by funding this work at http://www.paypal.me/mattneub. Or buy my books: the current (and final) editions are iOS 15 Programming Fundamentals with Swift and Programming iOS 14. Thank you!

Introducing Combine

Subscribers

Publishers

Operators

Transformers and Blockers

Accumulators

Partitioners

First and Last

Output

Prefix and Drop

Joiners

Splitters

Timers

Error Handlers

Codables

Threaders

Wrappers

Debuggers

Composed Operators

Custom Operators

Tricks and Tips

Partitioners

Partitioners
By partitioners, I mean operators that break off some subrange of the upstream values and emit those values. For example, the .first operator emits only the first value that arrives from upstream; the .output(at:n) operator emits only the nth value that arrives from upstream; and so on.

Like accumulators, some partitioners can emit a value only if the upstream sends a .finished completion. For example, the .last operator cannot know that it has received the last value from upstream until it also receives a .finished completion.

Prev: Collect

Next: First and Last

Table of Contents