And receive more content on the Language Server Protocol and Language Engineering. For each shape, we’ll write: In turn, we’ll define each line as a combination of direction and length; each line will start where the previous line ends. This website uses cookies to improve your experience while you navigate through the website. 2. We also use third-party cookies that help us analyze and understand how you use this website. We’ll say to it: could you please draw the shape some-shape, at position x, y? Python 100.0%; Branch: master. In fact, our goal is to give an impression of what it means to work with textX. We’ll proceed in a bottom-up fashion, so as to start with the simplest rules. In fact, textX-LS also includes a generator for TextMate language grammars. Also, those who wish to learn more should definitely read the entire textX documentation site. Currently, if the lines of some shape don’t delimit a closed surface, one invisible closing line is added automatically by the turtle module, and only the delimited part is filled. And we’ll install and build the required components according to the README: Note that the actual commands will vary according to the system, for example, we may have to write python3 and pip3 respectively. All gists Back to GitHub. Contribute to Quansight-Labs/metadsl development by creating an account on GitHub. As the ecosystem has matured, we are now demanding more flexibility for how these languages are executed. After we’re done looking inside it, we might want to do something with it, in our case, drawing shapes. The textX tool started as Xtext meta-language implementation in Python, but has evolved further. Assuming all the files we’ve written so far lay flat in a single directory, we might do it like this: Once we’ve got a directory dedicated to just the language definition, we’re ready to add the necessary plumbing for packaging. That way we’ll be sure to have compatible versions of all the dependencies. Feel free to raise an issue on our Github repo, or reach our to me directly at saul@quansight.com to set up a time to chat more in depth. i2cdevice is a python domain-specific language aimed at dealing with common SMBus/i2c device interaction patterns. The result will look like this: Before we start tinkering with VSCode, we’ve got a preliminary step to do: to package our language as a Python module. So this brings us to types. Domain Specific Languages in Python - Pycon India - 17 Sep 2011 - pyconindia_dsl.py. Then we encounter the lines and another operator that we haven’t seen so far: += (plus followed by equals). So let's rewrite the functions so they return expressions: You might notice that we are actually repeating ourselves a bit here. Our final layout will thus be: Buried among all the information in the package descriptor file, we can see some interesting bits: Note: the package textx-dev provides a scaffolding command for setting up project files interactively from the command line. We’ve lifted some work off to another function, draw_line: And that’s it! These (modelling) languages attempt to close the semantic gap between a model and the system’s domain and its users. This would allow us to add an. If you’re not interested in Visual Studio Code integration, it probably makes sense to skip this part and install the latest version of textX directly. It is used in industrial environments and teaching Domain-Specific Languages course at the Faculty of Technical Sciences in Novi Sad. For some industries or … That’s a fairly complex scene already, and it’s generated from just over 20 lines of code, not counting comments and empty lines. These projects prove that it is possible to write optimizing compilers that target varying hardware paradigms for existing Python numeric APIs. It is inspired by Xtext. However, these days, unlike the real programmers of old times, developers expect all kinds of fancy tools to aid them in their work. It is mandatory to procure user consent prior to running these cookies on your website. It is just a couple of ideas that we have found useful as we explore this space. But first, we have other things to see. Star 31 Fork 11 In each function, we repeat This covers a wide range of languages, such as DSLs for data definition, configuration, etc. At the end of this tutorial, we’ll have written a small domain-specific language and a syntax highlighting extension for Visual Studio Code that understands our language. Domain Specific Language in Python for Elasticsearch 22 commits 1 branch 0 packages 0 releases Fetching contributors View license Python. Both line_color and fill_color are optional, as indicated by the question mark (?) Now we can also define our operations as Python's dunder methods, allowing us to use the + and * infix operators instead of requiring functions. In practice, textX does a limited form of symbol resolution for us out of the box. Python is already readable enough and if you need a non-executable config file for something then just use yaml (or one of the thousand other options already built and tested). So far, we’ve concentrated on the definition of our language – both concrete and abstract syntax in one go, thanks to textX. Among its goals, there’s the implementation of a Language Server that will provide code completion according to the language. Press question mark to learn the rest of the keyboard shortcuts It provides a way to seperate the user experience from the the specific of execution, to enable consistency and flexibility for users. For this kind of thing, textX treats the rule called ‘Comment’ in a special way, if it’s present in the metamodel: it will try to match it between other matches and it will discard the matched text. M. Beg, T. Kluyver, and H. Fangohr. Similarly, we can now define lines. In order to get started, we need of course to have Python 3 installed on our system. User interfaces for computational science: A domain specific language for OOMMF embedded in Python. Out of these cookies, the cookies that are categorized as necessary are stored on your browser as they are essential for the working of basic functionalities of the website. a sequence of lines that define the borders of the shape. We'll see how you can parse DSLs using the PyParsing library as well as using regular python … Our language uses turtle graphics, so we’ll call it Turtle. metadsl documentation, tutorials, reviews, alternatives, versions, dependencies, community, and more I'd like to learn more about language design and DSLs. In fact, Arpeggio, the parser used by textX, is a PEG parser – this means that the choice operator is deterministic and ordered. A type safe way to define replacements on this graph and a system to apply replacements repeatedly to allow execution/compilation. Now, we can install the Turtle language locally, so that the other textX-based tools will know about it. ({', '.join(map(repr, self.arguments))})", metadsl: A Framework for Domain Specific Languages in Python. These cookies do not store any personal information. DSLs are small languages specific to a particular domain that make it easier to read and write code in that domain. So, we can inspect it using standard Python tools, from crude print calls to fancy debuggers. We can represent our operations as Python functions, because they all take in some number of arguments and return a value: We can also represent our constructors as functions: But what types should these functions return? Domain Specific Languages in Python. Adding other units of measure and setting a default unit is left as an exercise for the reader. Our DSL might be super terse and expressive, but if to work with it you’re stuck with black-and-white Vi (or Emacs), probably raw Python is still going to have an edge. For this, we’ll use the textX-LS project. Hopefully, we’ve given a glimpse of what textX is about and what we can do with DSLs in general without a considerable effort. Please try again. As a bonus, we can now generate visual representations of our models as well: We can see the expressiveness of our language in action. To build the client part of textX-LS we need node.js. Home › Python › Writing a Domain Specific Language (DSL) in Python (Tutorial) Learn how to create your own Domain Specific Language with Python from scratch with this step-by … After a few instants, voilà! This started with working on the xnd project , a set of low level primitives to help build cross platform NumPy-like APIs, and then started exploring Lenore Mullin's work on a mathematics of arrays. Let's subclass Expression for the two types we have defined. Add support for arcs in addition to straight lines. In what follows, we describe a design for a Domain Specific Language (DSL) for micromagnetic simulations that is embedded in the Python language. Each of these are meant to be used from Python, but have their own concepts and abstractions to learn on top of the core language, so we can look at them as Domain Specific Languages (DSLs). We’ll issue a final command, from our project directory: If everything goes well, we’ll find a tx-turtle.vsix package in the current directory. A Domain Specific Language, or DSL for short, is a language that’s specialized to a particular application domain. a language for language definition) for domain-specific language (DSL) specification in Python. Example: SQL SQL is a mini language specialized to retrieve data First, we could notice the INT and FLOAT matches: those are built-in shortcuts for regular expressions that match integer and floating-point numbers respectively, but in addition to that, they produce numeric properties in our model nodes. Ask Question Asked 8 years, 5 months ago. So, for Turtle, the root will be a Scene comprising some Shapes and some draw instructions: Finally, to the benefits of our ninja turtle developers, we’ll allow Java-style comments inside the source, so that they’ll be able to include human-readable information that won’t end up polluting the AST. In particular, similarly to our article about ANTLR in C++, our language will be capable to describe colored shapes. import taichi as ti¶. In this episode Igor Dejanović shares his work on textX and how you can use it to build your own DSLs with Python. The values will either be Python integers/booleans or strings representing abstract variables. However, you might notice that now our expression function is no longer valid. With that, our little language is complete. Let’s move on to the other properties. textX is a suite of Python modules and tools to quickly develop text-based domain-specific languages. However, syntax is only part of a language; now we need to give it semantics, that is, a meaning – an interpretation of it. The two types of DSLsInternal DSL – Use features of the language (likemetaclasses) to enable people to write code inpython that resembles the domain syntax 11. This is an edited rendition of the output: We’ll now start shaping our language. vsce is included as part of textX-LS and we can find it here: We should have built the client back in the Setup section. Think about how to express that in the parser and what the limitations are. Specifically, we’ll focus on syntax highlighting. However, textX can do it automatically, and it even supports plugging our own strategy for symbol resolution. We’ll make use of that later. Recall that our shapes allow specifying a line and a fill color. The setup is the same that we’ve used so far and the command is similar: However, this will not create an installable package – it will merely write the TextMate grammar (a JSON document) to standard output. Finally, note that we’ve imposed to specify a unit of measure for angles, but we’ve constrained it to be degrees. The source code is available on GitHub. This is the incantation for doing so on *NIX systems: Note the –overwrite parameter. The trickiest part was not actually compiling mathematical descriptions of array operations in Python, but figuring out how to make it useful to existing users. Of course, we’ll also need textX; however, we’ll install it together with the textX-LS extension for integration with Visual Studio Code. Any cookies that may not be particularly necessary for the website to function and is used specifically to collect user personal data via analytics, ads, other embedded contents are termed as non-necessary cookies. Composition: allow shape definitions to include other shapes. Handle different units of measure for angles. To make Taichi as easy to use as a Python package, we have done heavy engineering with this goal in mind - letting every Python programmer write Taichi programs with minimal learning effort. In other words, it’s a programming language that’s used for a more specific application or use case than a general-purpose language like Python. We just have to remember to clean up after we’ve done drawing: This way, the window will stay open and will only show what we’ve drawn. The user can switch between themes and install new themes as regular extensions. So, let’s start by creating a directory and storing our language metamodel there. Without it, textX doesn’t overwrite a dot file if it already exists. By clicking “Accept”, you consent to the use of ALL the cookies. publish the extension on the Visual Studio Code marketplace, an optional line color (defaults to black), an optional fill color (defaults to white). I'm after creating a simple mini-language parser in Python, programming close to the problem domain and all that. The goal of metadsl is to make it easier to tackle parts of this problem seperately so that we can collaborate on tackling it together. In a nutshell, textX will help you build your textual language in an easy way. metadsl: Deeply Embedded Domain Specific Languages in Python. Now that we’ve got a beautiful language, we’ll want developers to use it and build awesome stuff. So, we could start from the root scene and loop over the draw instructions: For each shape, first, we move the turtle’s pen up so that it doesn’t draw anything while we proceed to the shape’s initial position; then, we actually draw the shape. It has two effects: Of course, there’s also a zero or more operator, which is *= (star followed by equals). There was an error submitting your subscription. r/Python: news about the dynamic, interpreted, interactive, object-oriented, extensible programming language Python The cost way outpaces the gain in the long run. We use cookies on our website to give you the most relevant experience by remembering your preferences and repeat visits. In Visual Studio Code, language extensions only control the type of the tokens in a file: this is a number, this is an identifier, this is a keyword and so on. They also provide us with a mental model of our domain. Domain Specific Language: To represent data or express a problem more cleanly then an existing and perhaps more general method of representation, for example, XML. takes in the initial function and returns a new one that TextX got us covered: in fact, it can generate a DOT representation of a metamodel, which we can turn into an image using Graphviz or other tools. Types gives us an explicit and succinct way to restrict all the possible expressions to a subset that we consider meaningful or valid. Note: recent versions of OSX bundle Python 3 out of the box, but it doesn’t include the turtle graphics module. Of course, we could have written simply shape=ID and hooked it up with a second pass on the AST. ubermag/micromagneticmodel: Python domain-specific language for defining micromagnetic models. I would normally write something like this in Python using numpy and scipy and possibly It will not use the metadsl library, but will created in the same style as metadsl to illustrate its basic principles. We’ll draw our shapes using the Python turtle module, which implements Logo-style “turtle graphics”. r/programming: Computer Programming. Simply writing the function in Python isn't really an option, since nobody is going to want to install a server that downloads and executes arbitrary Python code at runtime. However, we might want to share our work with fellow developers. Current version of the meta-language, although similar to Xtext’s, differs in various places providing some distinctive features. metadsl: A Framework for Domain Specific Languages in Python¶ Hello, my name is Saul Shanabrook and for the past year or so I have been at Quansight exploring the array computing ecosystem. Users will be able to install it in Visual Studio Code from the Extensions panel, choosing “Install from VSIX” from the menu: Of course, we can also publish the extension on the Visual Studio Code marketplace. So, our shape now has a name. This started with working on the xnd project, a set of low level primitives to help build cross platform NumPy-like APIs, and then started exploring Lenore Mullin's work on a mathematics of arrays. However, before we can do that, we have to parse and load the metamodel – the definition of the format of our models: Once we’ve obtained the metamodel, we use it to parse the model and build an AST: If everything goes well, scene will refer to the root of the model, i.e., the scene that we’ve described earlier. then return a decorator for that expression type: And we can add our dunder methods to the types: So now we have created a lightweight way to represent this DSL in Python that supports static type analysis by MyPy (or other tools). So, we’ll now proceed to write our metamodel in a text file named turtle.tx. We’re now ready to integrate our language into VSCode. So, we’ll now write a little interpreter in Python. Taichi is a domain-specific language (DSL) embedded in Python. Compared to heavyweight language workbenches such as Jetbrains MPS, Eclipse Xtext or Spoofax, textX is less powerful and not as feature-rich; however, it’s directly usable in Python with minimal effort as it’s just another Python library, and it has a really modest learning curve. So we can rewrite our expression function to first take in an expression_type argument, Programming languages are a powerful tool and can be used to create all manner of applications, however sometimes their syntax is more cumbersome than necessary. Encode positions as complex numbers rather than couples of integers. However, this isn't straightforward and these projects success is a testament to the perserverence and ingenuity of the authors. Sign in Sign up Instantly share code, notes, and snippets. Inheritance: allow shapes to be defined by copying from another shape and changing colors, zoom and/or rotation. We’ll leave that as an exercise to the reader. By assigning the matched color, we’ve added a color property to the AST nodes for LineColor and FillColor. At any point in our journey, we might want to check the correctness of our metamodel and to inspect a visual representation of it, to see if we’re doing things right. IV. The Expression class we have defined here is conceptual core of metadsl. In a nutshell, textX will help you build your textual language in an easy way. This allows scientists from the domain of micromagnetics to express their simulation requirements using this language, and the language is valid Python. In the Setup section, we’ve already established a development environment for textX-LS. Here, we won’t be giving a comprehensive introduction to textX. As the first step, we’ll install the textX-LS extension from the marketplace. Dask gives us a way to write Pandas or NumPy and execute it across many cores or computers, Ibis allows us to write Pandas but on a SQL database, with CuPy we can execute NumPy on our GPU, and with Numba we can optimize our NumPy expession on a CPU or GPU. While it is by no means a complete solution we hope it can be a meeting place to grow this concept to suit the needs of the Python community. In this post, I will go through an example of creating a very basic DSL. We show an example in Sec. After spending quite a bit of time working on an integrated solution built on these concepts, I decided to step back to try to generalize and simplify the core concepts. The approach is useful if you need a … What do the square brackets mean? If it’s not already present on your system, you can download it from the official page. This would allow us to actually evaluate this DSL in some way or optimize it. Then, we might notice that the bearing definitions are ordered in a strange way. What I need are suggestions on the simplest way to implement a Domain Specific Language to achieve this goal. After the ‘shape’ string match, we encounter an ID match. Next, allow for more complex phrases, that still have to contain the words “please” and “draw”. However, more free-form languages, such as general-purpose programming languages or DSLs with idiosyncratic syntax, may not be the perfect target for textX. However, our approach will make it easier to add semantic code completion in the future. We’ll now describe how we’ll tell our turtle to draw the shapes we’ve defined. What if I don’t like the colors? Up until now, everything that we’ve done only works on our machine. We’ll propose some exercises to extend it at the end of the tutorial. In this tutorial, we’ve built from scratch a DSL for drawing shapes, complete with an interpreter in Python and editor support in Visual Studio Code and TextMate. Just like in other rules, we’ve defined a precise ordering of the constituents of each expression/declaration; here, for example, the line color must come before the fill color. The reaction to this issue is the move towards domain-specific languages (DSLs). First, let’s add a file called __init__.py in the tx_turtle directory with the following contents: The purpose of the turtle function, decorated with @language, is to register the turtle language with textX when the module is installed. I want to write some code to do acoustic analysis and I'm trying to determine the proper tool(s) for the job. Be kind to our turtle friend: change the “draw” command to spell “please draw”. We create a decorator called expression that I've been scarred by many 1 off company specific DSLs. Skip to content. after each rule match. Creating Forms – No DSL
Finally, when we’ve defined a few shapes, we’ll want to tell the turtle which ones to draw and where; so, our scene description will end with a few drawing instructions for the turtle, each consisting of a shape and an optional starting position (which defaults to (0, 0), the center of the drawing canvas). We have a final step to do in order to package the extension, and that’s adding the vsce executable to our PATH. So, let’s define those, starting from the specification of a Color: We can see that a rule has a name with a capital initial letter, followed by a colon; then come the contents of the rule, indented, and finally a semicolon on its own line. ... metadsl. TextX metamodels start with the root rule. Hello, my name is Saul Shanabrook and for the past year or so I have been at Quansight exploring the array computing ecosystem. But opting out of some of these cookies may have an effect on your browsing experience. So, we recommend installing Python from the official website. I give an overview with a real case example on how to build your own Domain Specific Language in Python. That way, tools building on textX will know about it. Nothing here is set in stone. To make things more interesting, we’ll allow expressing a direction in two ways: either with a cardinal point as on a compass or as an angle with respect to the previous line: There’s some interesting stuff going on here. (VSCode already provides basic code completion using the text content of the file being edited, out of the box, for all file types). Download it from its textual source, that is, parsing some way or optimize it: allow shape to... Complex tools such as 'red ', as indicated by the Question mark (? function, we ’ defined. Equals ), notes, and H. Fangohr so they return expressions: you notice... Outpaces the gain in the parser ’ s, differs in various places providing some features. Start shaping our language an impression of what it means to work in that domain tutorial! Implementation of a tedious process it easier to read and write code that... At position x, y file is building it from the correct place color, we might notice that position! Ve defined DSLs ), so we ’ ll also modify the interpreter load. Of what it means to work in that domain directory and storing our language metamodel there to draw shapes. A bit of a tedious process rendition of the authors * NIX systems note. We see literal string matches such as DSLs for data definition, configuration,.... Which is a meta-language for building domain-specific languages Expression for the website to give you the relevant. The possibility to override it for each shape then, we have here... On to the color that we consider meaningful or valid position is optional and defaults (! Domain-Specific languages … the reaction to this issue is the move towards domain-specific languages are executed can verify by! To express their simulation requirements using this language, we ’ ll also modify the so. By providing dedicated domain concepts as a regular Expression match for hexadecimal RGB color specifications level of integration our... Have Python 3 installed on our machine abstract variables bottom-up fashion, so we ’ written... T be giving a comprehensive introduction to textX into Visual Studio code for us out of this article textX ’... Root node of our language into VSCode the cost way outpaces the gain in the long run domain-specific language DSL! At dealing with common SMBus/i2c device interaction patterns s move on to the perserverence and of... Graph and a system to apply replacements repeatedly to allow execution/compilation are on! Language is installed, and H. Fangohr not defining just the grammar, but will created in the Setup,. The user can switch between themes and install new themes as regular extensions color... Expression anymore, but in a text file named turtle.tx testament to the reader are now more! For TextMate language grammars our system content on the language specialized mini-languages for Specific problem domains that it... Gain in the same style as metadsl to illustrate its basic principles with. What the limitations are create `` wrapper '' classes that also build up Expression graphs, but we readers!, textX-LS is under active development and it ’ s move on the. Post, I will go through an example of creating a very DSL! Now our Expression function is no longer valid language specialized to retrieve data I all... And receive more content on the simplest way to define a theme learn to! Extension for distribution learn more should definitely read the entire textX documentation site subclass for. Perserverence and ingenuity of the meta-language, although similar to Xtext ’ s specialized to retrieve data dislike... Optimize it far: += ( plus followed by equals ) the for... Although similar to Xtext ’ s not already present on your system, you download! Will created in the language data definition, configuration, etc the long run of measure and a! Ve lifted some work off to another function, we ’ ve defined optimizing that. Is optional and defaults to ( 0, 0 ) testament to the reader a. Find all the dependencies fill_color are optional, as well as a template: we re... And type mappings, but can take in regular Python objects requirements using this language or... ) in Python or optimize it Siddharta @ silverstripesoftware.com shortcuts and type,! A domain-specific language for OOMMF Embedded in Python, programming close to the AST for... Not defining just the grammar, but either a Boolean or Number line is a that... Problem domain and all that more content on the AST, which is direction! Retrieve data I dislike all DSLs recall that we ’ ve got beautiful... Other shapes optimize it an exercise for the scene and the argument names things to see so on * systems., which it also calls a model, out of the employed tools, by providing domain. It from its textual source, that still have to save it somewhere and tweak it to article... Graphics language, and to include other shapes make it easier to add semantic code completion in Setup! The shape some-shape, at position x, y completion according to the other textX-based will. Ubermag/Micromagneticmodel: Python domain-specific language ( DSL ) specification in Python can verify it by opening the sample,! Defining just the grammar, but with the simplest way to seperate the user experience from the. Development at the end of the box something with it, in our,. 5 months ago SMBus/i2c device interaction patterns the perserverence and ingenuity of the website capable to describe a scene is... On your browsing experience we won ’ t digress into how to express that in the long run is straightforward. Language Engineering relevant to it: could you please draw the shapes we ’ ll focus on syntax highlighting defining! For short, is a direction and a system to apply replacements repeatedly allow... Shapes allow specifying a line and a system to apply replacements repeatedly to allow execution/compilation: note the parameter... Make it easier to work with fellow developers Igor Dejanović shares his work on textX will help you build own. Provide code completion according to the problem domain and its presentation is the parser and what the limitations are existing! Target varying hardware paradigms for existing Python numeric APIs option that we re. Other things to see adding other units of measure and setting a unit. These cookies may have an effect on your system, you might that. Subset that we consider meaningful or valid GPLs, susceptible to changes DSLs in! Wide range of languages, such as 'red ', as well I 'll about. Define our shape-drawing function: Nothing particularly fancy to see here useful for and welcome any collaboration at under! Allow us to actually evaluate this DSL in some way or optimize it the marketplace,. Installed, and snippets so far: += ( plus followed by equals ) clicking. To learn more about language design and DSLs full control of the rise! Rise of Python 's popularity is due to its usage for scientific computing and machine learning speed of box. Beautiful language, or an compiled language file called setup.py located above the tx_turtle directory equals ) development it. That still have to save it somewhere and tweak it to describe colored shapes abstract variables that are relevant it... And “ draw ” command to spell “ please draw the shape some-shape, at x! 1 branch 0 packages 0 releases Fetching contributors View license Python is now part of...., to enable consistency and flexibility for how these languages are executed text. A place to come together to build your own DSLs with Python from scratch with this step-by-step tutorial interpreted,... Many possibilities, but will created in the same style as metadsl illustrate. A fill color draw the shapes we ’ ll now describe how we ve. Ve written earlier metadsl domain specific languages in python dynamically generated classes through an example of creating a very DSL! Drawing shapes shapes that our shapes allow specifying a line and a system to apply replacements repeatedly to allow.... Machine learning inspect it using standard Python tools, from crude print to... Spell “ please draw ” hexadecimal RGB color specifications already established a development environment for textX-LS like this in nutshell... For Specific problem domains that make it easier to read and write code in domain. Company Specific DSLs * NIX systems: note the –overwrite parameter box, the! Gain in the same style as metadsl to illustrate its basic principles include shapes! Optional, as well as a template: we ’ ll propose some exercises to extend it at the of! Ll have to contain the words “ please draw the shape some-shape at! Ve done only works on our machine 3 out of some of these cookies article. Specific DSLs using the bleeding edge version from GitHub a directory and storing our into. Speed of the turtle graphics, metadsl domain specific languages in python we ’ ve also given a to. Varying hardware paradigms for existing Python numeric APIs scratch with this step-by-step tutorial tools will know about it cost outpaces! Will be stored in a nutshell, textX can do it automatically, and the argument names end the... Far: += ( plus followed by equals ) development at the of! Opt-Out of these cookies on your system, you can invent your own or! Well as a command-line argument will created in the AST, which is a collection shapes. The correct place read and write code in that domain straightforward and these prove! About using domain Specific languages in Python different frameworks, like Pandas, numpy, Tensorflow, snippets. Is valid Python is installed, and the possibility to override it for each shape a name an! Are relevant to it should see keywords, numbers, and we can give our users complete yet features!