langium-arithmetics-dsl

Arithmetics Example

Interpreter CLI

The Arithmetics Example features an interpreter that you can run via cli.

• Ensure the complete project was properly built, otherwise run npm install once in the root of the Langium project. That is enough, since we use npm workspaces to manage all of our npm projects as one monorepo.
• Run npm run build (again in the root directly) to actually generate the JavaScript code from the TypeScript sources.
• Use node ./bin/cli from the arithmetics directory to run the cli. Follow the instructions or use node ./bin/cli eval <full-path-to-calc-file>, e.g.

cd examples/arithmetics
node ./bin/cli eval example/example.calc

produces this result:

line 14: 2 * c ===> 16
line 15: b % 2 ===> 1
line 18: Root(D, 3) ===> 4.999999999999999
line 19: Root(64, 3) ===> 3.9999999999999996
line 20: Sqrt(81) ===> 9

The interpreter calculates each Evaluation in the source file and prints the result.

You also can use arithmetics-cli as a replacement for node ./bin/cli, if you install the cli globally.

• Run npm install -g ./ from the arithmetics directory.
• Use arithmetics-cli or arithmetics-cli eval <full-path-to-calc-file>.

VSCode Extension

Please use the VSCode run configuration "Run Arithmetics Extension" to launch a new VSCode instance including the extension for this language. Afterwards, use the run configuration "Attach" to attach the debugger to the running language server.