Custom Error Example - Anchor Typing CST Test

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Custom Error Example — Anchor Code

Demonstrates defining and using custom errors in Anchor.

#[program]
mod custom_error {
	use super::*;
	pub fn check_value(ctx: Context<Check>, value: u64) -> Result<()> {
		if value > 100 {
		return Err(ErrorCode::ValueTooHigh.into());
		}
		Ok(())
	}

	#[error_code]
	pub enum ErrorCode {
		#[msg("Value exceeds the allowed limit")]
		ValueTooHigh,
	}

	#[derive(Accounts)]
	pub struct Check<'info> {} 
}

Anchor Language Guide

Anchor is a Rust-based framework for Solana smart contract (program) development, testing, and deployment. It simplifies building Solana dApps by providing a high-level abstraction over Solana programs and client interactions.

Primary Use Cases

▸Writing Solana smart contracts in Rust
▸Generating client interfaces (IDL) for programs
▸Testing programs with simulated Solana clusters
▸Deploying Solana programs to devnet/testnet/mainnet
▸Automating transactions and client-side interactions

Notable Features

▸Rust-based Solana program development
▸IDL generation for client libraries
▸Anchor CLI for scaffolding, building, and deploying programs
▸Testing framework integrated with Solana local validator
▸Macros to reduce boilerplate for accounts, instructions, and errors

Origin & Creator

Anchor was created by Project Serum team members in 2020 to simplify Solana program development, reduce boilerplate, and improve developer productivity.

Industrial Note

Anchor is widely used in DeFi, NFT, and other Solana ecosystem projects, as it standardizes Solana program structure and automates common patterns like account validation and serialization.

Quick Explain

▸Anchor allows developers to write, test, and deploy Solana programs efficiently using Rust.
▸It provides scaffolding, IDL (Interface Definition Language) generation, and client SDKs for interacting with deployed programs.
▸Anchor streamlines Solana development by managing accounts, PDAs (Program Derived Addresses), and transaction boilerplate.

Core Features

▸Program scaffolding with `anchor init`
▸Program compilation and deployment via `anchor build`/`anchor deploy`
▸Type-safe client SDK generation (TypeScript, Rust)
▸Account serialization/deserialization helpers
▸Testing with local validator and program simulation

Learning Path

▸Learn Rust programming basics
▸Understand Solana accounts, PDAs, and transactions
▸Practice Anchor CLI and project workflow
▸Write automated tests using local validator
▸Deploy and interact with programs on devnet/mainnet

Practical Examples

▸Deploy a simple token program to local Solana validator
▸Write unit tests for program instructions
▸Interact with deployed program via TypeScript client
▸Generate IDL and use it for frontend integration
▸Deploy NFT minting program to devnet

Comparisons

▸Anchor vs Solana SDK: Anchor reduces boilerplate and manages accounts/PDAs
▸Anchor vs Metaplex CLI: Anchor focuses on program development; Metaplex is NFT-specific
▸Anchor vs Hardhat/Ethereum frameworks: Solana vs Ethereum ecosystem, Rust vs JS/Python
▸Anchor vs web3.js client: web3.js is only client, Anchor provides full program+client workflow
▸Anchor vs Serum SDK: Anchor is general-purpose; Serum SDK is DEX-specific

Strengths

▸Reduces boilerplate and enforces best practices
▸Simplifies account and PDA management
▸Strong testing support with local validator
▸IDL provides type-safe client interaction
▸Large adoption in Solana DeFi and NFT projects

Limitations

▸Only for Solana blockchain
▸Requires familiarity with Rust programming
▸Program size limitations dictated by Solana
▸Learning curve for Anchor-specific macros and patterns
▸Smaller ecosystem compared to Ethereum tooling like Hardhat/Brownie

When NOT to Use

▸If targeting blockchains other than Solana
▸For rapid prototyping without Rust knowledge
▸When minimal program deployment without IDL is sufficient
▸If using prebuilt programs and only client-side interaction is needed
▸Projects with team unfamiliar with Rust or Solana

Cheat Sheet

▸anchor init = create new project
▸anchor build = compile program
▸anchor test = run program tests
▸anchor deploy = deploy program to cluster
▸anchor upgrade = upgrade deployed program

FAQ

▸Is Anchor free?
▸Yes - open-source under Apache 2.0 license.
▸Which blockchain does Anchor support?
▸Solana (devnet, testnet, mainnet).
▸Can I deploy NFTs with Anchor?
▸Yes - supports NFT minting programs and Metaplex integration.
▸Does Anchor support automated testing?
▸Yes - integrated with local validator and test framework.
▸Can Anchor programs interact with DeFi protocols?
▸Yes - supports Serum, Raydium, and other Solana DeFi programs.

30-Day Skill Plan

▸Week 1: Anchor project setup and local validator testing
▸Week 2: Write and test simple token programs
▸Week 3: Learn PDAs, accounts, and error handling
▸Week 4: Deploy NFT or DeFi programs to devnet
▸Week 5: Integrate with TypeScript/React frontends using IDL

Final Summary

▸Anchor is a Rust framework for Solana smart contract development, testing, and deployment.
▸Reduces boilerplate and enforces best practices for program and account management.
▸IDL generation enables type-safe client interactions.
▸Supports testing with local validator and automated scripts.
▸Widely adopted in Solana DeFi, NFT, and general dApp ecosystems.

Project Structure

▸programs/ - Rust program files
▸tests/ - Rust test scripts for program instructions
▸migrations/ - deployment scripts
▸target/ - compiled binaries
▸Anchor.toml - project configuration and Solana cluster info

Monetization

▸Develop DeFi protocols
▸Launch NFT platforms
▸Provide Solana program development services
▸Offer consulting for Anchor-based dApps
▸Create client SDKs and automation tools

Productivity Tips

▸Use macros for repetitive account and instruction logic
▸Generate IDL for type-safe client integration
▸Leverage local validator for fast testing
▸Batch tests and transactions for efficiency
▸Use Anchor CLI for streamlined project workflow

Basic Concepts

▸Program: Solana smart contract written in Rust
▸Instruction: Function in a program invoked by a transaction
▸Account: Storage unit in Solana, holding data and SOL
▸PDA: Program Derived Address for deterministic account management
▸IDL: Interface Definition Language file describing the program

Official Docs

More Anchor Typing Exercises

Anchor Simple Counter Program Anchor Token Mint Example Anchor Initialize Account Example Anchor Transfer SOL Example Anchor PDA Example Anchor Multisig Example Anchor Escrow Example Anchor Event Emission Example Anchor Program With Seeds Example

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