First prototype of plaintextflow released

The mps-plaintextgen plugin has been upgraded with new functionality for fine-grained control of whitespaces. Such functionality is very useful for languages that are fiddly with whitespace such as reStructuredText or where you just want to have very fine control (such as in JSON or in some instances Python). Plaintextflow is part of the plaintextgen plugin, … Read more

Using the diagram editor and querylist: let’s build a graphical structure editor for MPS

Today, I am going to lead you through a tutorial of how to build a graphical (slightly UML-like) editor for the structure of an MPS language. The main goal of this tutorial is to show you how to use the diagram editor and querylist plugins that have been developed by Itemis¬†as part of the mbeddr … Read more

A common useful case for ‘can be parent’ constraints in MPS

Imagine you have a (very contrived) language as shown below (i.e. some root that contains children of an abstract concept named A and Bs and Cs extend A): By default, all As and Bs can be substituted (Ctrl/Cmd+Space) in the nlist of MyRoot: Now, if we want to restrict this, to, let’s say, only Bs, … Read more

Separate MPS caches for different MPS distributions based on the same MPS major version

Between MPS major versions, the MPS global caches are nicely separated (e.g. for MPS 2017.1, the cache directory is $HOME/.MPS2017.1 and for MPS 2017.2, the cache directory is $HOME/.MPS2017.2, where $HOME is your home directory, e.g. C:\Users\<yourusername> on Windows or /home/<yourusername> on Linux). Sometimes, there are reasons why you would want to change the cache … Read more

How I make an open source mbeddr developer release

The mbeddr RCP is great, because it gives you a focused MPS-based IDE, including mbeddr.platform, which you can use to write models in the embedded software domain. However, I find it often useful to have the mbeddr.platform plugins (which are generic pieces of functionality useful for any DSL development) available for development as a language … Read more

Language Visualization Plugin for JetBrains MPS

We just finished migrating the language visualization plugin to MPS 2017.3. This extension can visualize the structure of a language graphically, in order to give insight for new people learning a language, and to save effort in creating diagrams of a language. You will need PlantUML to make a picture of the language visualization. The … Read more

How to debug in MPS

The quickest way to start debugging in MPS is the following: We are using com.dslfoundry.plaintextgen as an example. Please be advised that in (possibly earlier) generic distribution versions of MPS, the debugger doesn’t work. You will have to really use one of the dedicated distributions (Mac, Linux, or Windows). Choose your breakpoint by clicking in … Read more