Primer is a pedagogical functional programming language. This repository contains a collection of React components to support Primer programming-related activities, including reading, writing, running, and debugging Primer programs. The project also provides a web application which integrates these components into a novel visual programming environment, featuring a tree-based structure editor.
For the moment, we're focusing on the development of the integrated web app, but our long-term goal is to make it possible to use the project's React components to integrate Primer programming activities into interactive applications and games.
The web app in this project currently requires that a Primer language
server instance is available. We provide a Haskell implementation of a
Primer language server in this project's companion repository,
primer. Both projects are
licensed under the terms of version 3 (or later) of the GNU Affero
General Public License, and can be freely copied, modified,
and distributed, so long as the license is preserved.
The Primer programming language, our Primer language server implementation, and this web app are all still under heavy development. Expect lots of breaking changes until we reach stable releases of all of these components. Please note that we don't currently have any accurate time estimates for when we expect to reach these milestones.
This web app, in particular, should be considered to be of alpha-release quality. There are many incomplete and altogether missing features, known bugs, and visual & usability defects. While it's already possible to write at least some Primer programs using this web app, please keep in mind the following important caveats about the current state of the project:
We've yet to do any rigorous testing of Primer with students, and none at all in classrooms. Primer may turn out not be an effective way to teach functional programming to novices! That said, if you're an educator and you'd like to know more about the limited testing we have done to date, please reach out to us. As some important features are still missing from the web app, we don't recommend that you try to use Primer for any serious teaching at this time.
At the moment, this project requires access to a Primer language server instance, so you should also familiarize yourself with that project's caveats, as well. Running a Primer language server instance is relatively easy if you're a developer, as we provide a Docker image for it, but we're aware that many educators may not have the time or knowledge to do this themselves. In the not-too-distant future, we hope to be able to run the development environment in the browser, without requiring a server instance.
All of our UX design has been done with accessibility (a11y) in mind, and our 1.0 release will have robust support for it, but the current implementation is lacking. As we're not a11y experts, if you'd like to make an important contribution to the project, this would be a particularly impactful area in which to do it.
One of the primary goals of the Primer programming language is to support programming activities in the student's native language, so that the ability to read and write English is not a prerequisite for learning to program. As such, the Primer language server API is mostly natural language-neutral; e.g., the API reports errors as symbolic values, rather than as text strings intended to be shown to the student verbatim. Full internationalization (i18n) support is left to clients of the Primer API, such as this web app. However, for practical and resource-related reasons, our initial web app implementation only fully supports English. We'll make a best-effort attempt to support a few other widely-spoken natural languages in our 1.0 release, and robust i18n support will be a high priority in post-1.0 releases, but this is another area in which community members could make an impactful contribution to the project.
At the moment, Primer is a pure functional programming language, with no effects system. This means, for example, it's not currently possible to draw animated cats using Primer. We plan to implement an effects system in version 2.0 of the language specification and this web app, but that will work will not begin for some time. Version 1.0 of Primer will focus on teaching fundamental functional programming concepts, such as functions, types, expressions, and program evaluation.
We welcome contributions from the community! Please read our contributing guide if you think you'd like to help.
We also provide a comprehensive development guide for anyone who'd like to build and run the project locally.
Some third-party assets that we distribute together with this
project's source code (e.g., open source fonts) are licensed
separately from the source code. For each such asset, there's a
corresponding license file in the licenses subdirectory of the
project.
We have also "vendored" some source code from third-party libraries; i.e., we have included a few third-party source code files directly in this project, rather than linking to them as a pre-built dependency. When this is the case, the source files will include their license and copyright notice directly in the source file.