This time we will talk about the critical lower-level function delegatecall. It is widely used in a proxy pattern, for instance, when using OpenZepplin upgrades pattern. Essentially this function executes code in another contract but uses data from the caller concept. Let's dig deeper and explore more. Storage clash When using delegatecall…

Do we want data to persist between calling the smart contract or being saved locally while executing the function? — This time, we will talk about storage locations in Solidity programming language, specifically about the storage and memory locations. Not knowing what they represent and how they work can cause issues in our smart contracts. Storage Storage in smart contracts holds data between function calls. We can imagine that storage would…

Events in Solidity programming language help inform when something has happened in the smart contract. Parties like a web frontend, data gathering tools, and more can listen to specific events and react accordingly. In this post, we will dig deeper into Events and how to use them when developing smart…

A look at Solidity’s approach to hash table — Mappings in Solidity programming language play a significant role. These are hash tables that can have a key and value. When we use them, there are some caveats, especially from other programming languages. Let’s explore them in this article. Mapping Keys and Values Mappings essentially are hash tables, so it means that the key…

Add, remove, modify elements — Arrays in Solidity programming language can hold primitive data types like integers, boolean, and string. An array can be initialized with a fixed or dynamic size. If we compare them to other more advanced programming languages, there are pretty limited functions available to work with arrays. …

Understand the different types of visibility in functions and state variables — Solidity language allows specifying accessibility for contract functions and state variables. That will enable us to set constraints on constructing the smart contract and whether other contracts or addresses can access the data. Contract state variables and functions have a slight difference that we’re going to check out. I want…

Get started with Solidity in Swift — Solidity is an object-oriented language to write smart contracts that can be deployed on the blockchain, for instance, Ethereum. The syntax is similar to Javascript, but on the other hand, semantics is closer to C++. We will dig into Solidity language structure and functions from a Swift developer’s perspective. Pragma and sfile extension Before…

Use the power of tab view for navigation — We learned how to add a sidebar for an iPad in the previous blog post, but that approach isn’t that great for an iPhone. It looks pretty weird, and once we configure a default view, it automatically navigates to it once iPhone app starts. This isn’t great on a phone…

Implement navigation for your iPadOS apps — Starting with iPadOS 14, Apple has redesigned the iPad sidebar by making it easier to navigate within an app. It’s explained in the Human Interface Guidelines and is already used in stock apps such as Photos, Files, Notes, Calendar, and more. In this article, let’s see how to build a…