Python for Excel Code Editor

January 18, 2025

Overview

We’re excited to announce a major update to our Python for Excel add-in that makes it easier than ever to create Excel LAMBDA functions from Python code. The new code editor provides a familiar VS Code-like experience right inside Excel, with features like syntax highlighting, function management, and integrated testing.

Key Features

Monaco Editor Integration

The add-in now includes the same editor (Monaco ) used in VS Code, providing:

• Syntax highlighting for Python
• Code completion and formatting
• Error detection

Function Management

A new Functions tab lets you:

• View all Python functions in your workbook
• Edit existing functions
• Delete unused functions
• Import functions from Jupyter notebooks

Testing Integration

Write test cases directly in your Python code:

def hello(first, last):
    """ Returns a greeting. """
    greeting = f"Hello {first, last}!"
    return greeting
    
# Test cases for the function
test_cases = [["Nancy", "Morgan"], ["Ming", "Lee"]]
 
# Excel usage: =HELLO("Nancy", "Morgan")

Click “Test” to run your cases and see results in the Output tab.

How It Works

Creating a Python-powered LAMBDA function is now a two-step process:

1. Write your Python function in the editor
2. Click Save to create the LAMBDA

The Python code is stored in workbook settings and a corresponding LAMBDA function is automatically created in Excel’s name manager. For example, this Python function:

def inches_to_mm(inches):
    """ Converts inches to millimeters. """
    return inches * 25.4

Creates this LAMBDA in Excel:

=LAMBDA(inches, BOARDFLARE.EXEC("workbook-settings:inches_to_mm", inches))

Jupyter Notebook Integration

A particularly exciting feature is the ability to import functions from Jupyter notebooks. You can:

• Import from our example notebooks
• Load notebooks from GitHub Gists
• Use the notebooks as templates for your own functions

This makes it easy to maintain a library of functions in notebooks and import them into Excel as needed.

Try It Out

To get started with the new code editor:

1. Install the Python for Excel add-in 
2. Open the task pane and go to the Editor tab
3. Try writing a simple function or import one of our examples
4. Click Save to create your LAMBDA function

The code editor is available now in version 1.1.0 of the add-in. For more details, check out our updated documentation.

What’s Next?

We’re continuing to improve the editor experience. Coming soon:

• Support for optional arguments
• More example notebooks
• Enhanced type conversion options

Let us know what features you’d like to see next!