2.3.3 Setting Up Visual Studio Code with Calva

Optimize Your Clojure Workflow with Calva in Visual Studio Code

Embarking on your Clojure journey requires the right tools for an efficient and productive workflow. Visual Studio Code, coupled with the Calva extension, provides a comprehensive setup that caters to all your Clojure programming needs—from interactive REPL sessions to robust debugging capabilities. In this guide, we will walk you through the installation and configuration processes, ensuring you are equipped with the best environment for your Clojure development.

Step 1: Install Visual Studio Code

Visual Studio Code is a lightweight yet powerful source code editor available on various platforms.

1. Download Visual Studio Code:

   • Visit the Visual Studio Code website.
   • Select the appropriate version for your operating system.
   • Follow the installation instructions specific to your operating system.

2. Launch VS Code:

   • Once installed, open Visual Studio Code to begin configuring your environment.

Step 2: Install the Calva Extension

Calva is an extension for Visual Studio Code that adds support for Clojure and ClojureScript.

1. Open Extensions View:

   • In Visual Studio Code, navigate to the sidebar and click on the Extensions icon or press Ctrl+Shift+X.

2. Search for Calva:

   • Type “Calva” in the search bar.
   • Locate “Calva: Clojure & ClojureScript Interactive Programming” in the search results.

3. Install Calva:

   • Click the install button for the Calva extension.

Step 3: Configure Calva Settings

Optimizing Calva settings enhances your coding experience.

1. Access Settings:

   • Go to File > Preferences > Settings or press Ctrl+,.

2. Configure Recommended Settings:

   • Search for Calva settings by typing “Calva” in the settings search bar.

   • Adjust key settings such as:

     • Calva: Format on Save: Enable to automatically format code upon saving.
     • Calva: Eval on Save: Optionally enable to evaluate code on save, useful for continuous feedback.
     • Calva: Trace App Output: Enable for more detailed debugging information.

Step 4: Start a REPL Session

Interactive REPL sessions allow you to run and test your Clojure code dynamically.

1. Open the command palette:

   • Use Ctrl+Shift+P.

2. Start the REPL:

   • Type “Start a Project REPL and Connect (aka Jack-in)” and select the option that appears.
   • Choose the REPL configuration that matches your project.

3. Evaluate Code:

   • Open a Clojure file.
   • Highlight a section of code or place the cursor within an expression.
   • Press Ctrl+Enter to evaluate the code in the REPL.

Step 5: Use Debugging Tools

Calva’s debugging tools can identify issues and optimize code behavior.

1. Add Breakpoints:

   • Click in the gutter next to the line numbers in your Clojure file to set a breakpoint.

2. Debug:

   • Run the command “Calva: Run Tests” or “Calva: Evaluate Current Form” with debugging.

3. Inspect Variables:

   • Hover over variables during a breakpoint to view their current values.

With Visual Studio Code and Calva configured, you’ve set the stage for a streamlined and efficient Clojure development experience. Dive into the world of functional programming with confidence, equipped with powerful tools to explore, experiment, and debug your code.

Now, test your understanding and ensure everything is set up correctly with the quiz below!

Set up your environment now and explore the potential of functional programming with Clojure!