Microsoft Visual Studio Code (VS Code) & IBM i

IBM i (formerly AS/400, iSeries, System i) is a highly secure and stable enterprise computing system used for mission-critical applications in industries like banking, insurance, retail, logistics, and manufacturing. Traditionally, development on IBM i relied on tools like SEU, PDM, and RDi. However, with IBM’s growing support for open-source tools, Microsoft Visual Studio Code (VS Code) has emerged as a modern alternative, offering an efficient and flexible workflow for RPG, COBOL, CL, and SQL development. By integrating seamlessly with IBM i, VS Code enables developers to write, edit, debug, and deploy code while maintaining legacy RPGLE and COBOL applications. Its rich extension ecosystem enhances productivity, streamlines development, and provides a modern IDE experience. This shift to VS Code modernizes IBM i development, allowing teams to adopt contemporary DevOps practices while leveraging the platform’s reliability and security.

What is Visual Studio Code (VS Code)?

Visual Studio Code (VS Code) is a free, open-source, and lightweight code editor developed by Microsoft. It is designed for efficient coding, debugging, and development across multiple programming languages. Unlike full-fledged IDEs like Visual Studio or Eclipse, VS Code provides a minimalist yet powerful environment with high performance and flexibility. It is available on Windows, macOS, and Linux.

Key Features of VS Code:

1. Multi-Language Support

VS Code supports various programming languages natively, including:

• Web Development: HTML, CSS, JavaScript, TypeScript
• Back-End Development: Python, Java, C++, PHP, Go, Node.js
• Enterprise & Legacy Systems: RPGLE, COBOL, CL, SQL (used in IBM i development)
• Cloud & DevOps: YAML, Docker, Kubernetes

2. IntelliSense (Advanced Code Editing & Autocomplete)

• Offers smart code completion, syntax highlighting, and real-time suggestions.
• Uses AI-powered analysis to predict and suggest the next line of code.
• Supports error detection and inline warnings for better productivity.

3. Integrated Git & Version Control

• Built-in Git support for version control directly within the editor.
• Allows staging, committing, pulling, and pushing changes to repositories.
• Integrates with GitHub, GitLab, Azure DevOps, and Bitbucket.

4. Debugging Capabilities

• Powerful built-in debugger with breakpoints, call stack, and variable tracking.
• Supports debugging for JavaScript, Python, C++, Java, and more.
• Provides interactive debugging with an integrated console.

5. Extensions Marketplace

• Offers thousands of extensions for additional functionalities.
• Includes language packs, themes, AI-powered coding assistants, and more.
• Supports IBM i (AS/400) extensions for RPG, COBOL, CL, and SQL development.

6. Remote Development & Cloud Integration

• Connects to remote servers and virtual machines for direct coding.
• Works with WSL(Windows Subsystem for Linux) and SSH connections.
• Compatible with Docker and Kubernetes for cloud-native development.

7. Built-in Terminal

• Provides an integrated command-line terminal for executing commands.
• Supports PowerShell, Bash, and command-line tools.
• Helps developers run scripts and interact with version control efficiently.

Why is VS Code Popular?

• Lightweight & Fast – Unlike traditional IDEs, VS Code runs smoothly without consuming excessive system resources.
• Highly Customizable – Developers can modify themes, shortcuts, and add plugins as needed.
• Cross-Platform Compatibility – Works across Windows, macOS, and Linux environments.
• Strong Community Support – Backed by Microsoft and widely adopted in the developer community.

VS Code for IBM i (AS/400) Development

With IBM’s increasing support for open-source tools, VS Code has become a preferred choice for IBM i (AS/400) development. By installing the right extensions, developers can

• Write, edit, and debug RPGLE, COBOL, CL, and SQL code directly on IBM i.
• Use modern DevOps practices while maintaining legacy applications.
• Improve workflow efficiency by integrating VS Code with IBM i’s runtime environment.

How VS Code Can Help You Write Modern RPGLE Code

IBM i (AS/400) development has long relied on traditional tools, but Visual Studio Code (VS Code) offers a modern, flexible alternative. With the right extensions, VS Code enhances RPGLE development by improving code readability, debugging, error detection, and remote access. It streamlines collaboration and deployment, making RPGLE programming more efficient and aligned with contemporary DevOps practices. By switching to VS Code, IBM i developers can embrace a feature-rich environment that boosts productivity and modernization.

Key Benefits of Using VS Code for RPGLE Development

1. Modern Code Editing Experience

• Syntax Highlighting: Makes RPGLE code more readable and structured.
• IntelliSense: Provides real-time suggestions, auto-completion, and inline documentation for RPGLE.
• Bracket & Block Matching: Helps identify beginning and ending blocks in complex RPGLE programs.

2. RPGLE Code Debugging & Error Detection

• Integrated Debugger: Allows setting breakpoints, inspecting variables, and stepping through code.
• Linting & Error Checking: Highlights syntax errors, unused variables, and logic issues before compilation.
• Code Navigation: Jump to function definitions, declarations, and references quickly.

3. Seamless IBM i Integration

• Remote Development: Connects directly to IBM i (AS/400) servers using SSH or specialized IBM i extensions.
• Direct Editing & Uploading: Modify RPGLE source code on the server without downloading files manually.
• Command Execution: Run IBM i CL commands, SQL queries, and PDM operations directly from VS Code’s terminal.

4. Git Integration for Version Control

• Track Code Changes: Manage RPGLE code using Git repositories (GitHub, GitLab, Bitbucket, or Azure DevOps).
• Collaborative Development: Multiple developers can work on RPGLE programs simultaneously.
• Easy Rollbacks: Quickly revert to previous versions of code without losing important changes.

5. IBM i – Specific Extensions for RPGLE

• Code for IBM i Extension: Provides direct connectivity to IBM i, supporting RPGLE, CL, COBOL, and SQL development.
• DB2 & SQL Support: Query IBM i databases (DB2 for i) directly from VS Code.
• IBMi-CLI Integration: Run IBM i commands without switching between multiple interfaces.

6. Increased Productivity & Efficiency

• Multi-File Editing: Open multiple RPGLE programs side by side for better debugging and cross-referencing.
• Task Automation: Automate build, deploy, and testing tasks for RPGLE using VS Code’s task system.
• Customizable Shortcuts: Create personalized keyboard shortcuts and macros for faster development.

Advantages & Disadvantages of Using IBM i on VS Code

IBM i (AS/400) development has traditionally relied on older tools, however with Microsoft Visual Studio Code (VS Code) and IBM i-specific extensions, developers can now use a modern, lightweight, and feature-rich environment for RPGLE, COBOL, CL, and SQL development. Below are the key advantages and disadvantages of using VS Code for IBM i development.

• Advantages of Using IBM i on VS Code

1. Modern Development Experience

• VS Code offers a better UI, faster performance, and a moreintuitive workflow.
• Features like syntax highlighting, IntelliSense, auto-completion, and bracket matching improve coding efficiency.

2. Remote Development Capabilities

• Connects to IBM i servers directly via SSH or through IBM i-specific extensions like Code for IBM i.
• Edit, compile, and debug RPGLE, CL, and COBOL code without needing to log in to a 5250 session.

3. Built-in Debugging & Error Detection

• Integrated debugger for RPGLE, COBOL, and SQL with support for breakpoints, variable inspection, and call stack tracking.
• Real-time linting helps detect syntax errors and logical issues before compilation.

4. Git & Version Control Support

• VS Code integrates seamlessly with Git, allowing developers to track changes, collaborate, and manage code versions.
• Supports GitHub, GitLab, Azure DevOps, and Bitbucket for code management.

5. Extensibility & Customization

• Thousands of extensions available in the VS Code marketplace to enhance IBM i development.
• Supports theme customization, keyboard shortcuts, and task automation.

6. Cross-Platform Availability

• Works on Windows, macOS, and Linux, providing flexibility to developers using different operating systems.
• Eliminates the need for IBM i-specific IDEs like RDi, which are limited to certain platforms.

7. Integration with Modern DevOps & CI/CD Pipelines

• Supports DevOps workflows, including automated builds, testing, and deployments for IBM i applications.
• Can be used with Jenkins, GitHub Actions, and Azure Pipelines for continuous integration.

• Disadvantages of Using IBM i on VS Code

1. Requires Setup & Configuration

• Unlike SEU or RDi, VS Code does not natively support IBM i; it requires extensions (e.g., Code for IBM i).
• Developers need to manually configure IBM i connections, compilers, and debugging tools.

2. Limited Native Support for IBM i Features

• VS Code does not support all IBM i-specific functionalities out of the box.
• Some advanced features of RDi, like graphical DDS designers and visual screen editors, are missing.

3. No Built-in IBM i Database Navigator

• Unlike RDi, VS Code does not have an integrated DB2 for i database navigator for managing tables, indexes, and queries.
• Developers must use separate database extensions or external tools for DB2 interaction.

4. Debugging Limitations for Complex RPG Programs

• While debugging is supported, stepping through complex RPGLE programs is not as smooth as in RDi.
• Limited support for interactive debugging compared to IBM’s native tools.

5. Learning Curve for Traditional IBM i Developers

• Requires knowledge of Git, JSON-based configurations, and remote development workflows.

6. Dependency on Extensions

• VS Code’s functionality for IBM i relies heavily on third-party extensions.
• If IBM i-specific extensions are not actively maintained, functionality may break with future updates.

Conclusion:

IBM i (AS/400) development is being revolutionized by Visual Studio Code (VS Code), which provides a cutting-edge, effective, and highly configurable environment. With the help of tools like debugging, Git integration, IntelliSense, and IBM i-specific extensions, developers can now embrace contemporary DevOps procedures while maintaining classic RPGLE and COBOL code. It is a potent substitute for more conventional tools like SEU and RDi because of its cross-platform compatibility, remote access, and extension marketplace. The overall advantages in productivity and modernity exceed the disadvantages, even when setup and certain native IBM i functions could be restricted. One innovative option for enterprise IBM i development is Visual Studio Code.