c-slang

Calculator language modified from js-slang.

Possible Issues (and manual solutions)

* If you failed to execute the jsdoc.sh in your bash
* Delete the first line of jsdoc.sh (for Windows PowerShell) before executing yarn jsdoc.
* Please modify the line break type if ‘bash\r’: No such file or directory
* node should be replaced by node.exe if you are using WSL with node.js installed on your Windows.
In case you meet the same error as this when using node-getopt*, modify the package.json of node-getopt as this PR shows.

Table of Contents

- Requirements
- Usage
- Documentation
- Requirements
- Testing
- Error messages
- Using your xx-slang in your local Source Academy
- Talks and Presentations
- License

Requirements

- node: known working version: v16.14.0

Usage

To build,

``{.}
$ git clone https://github.com/yangdinglou/c-slang
$ cd c-slang
$ yarn
$ yarn build
`

To add \"c-slang\" to your PATH, build it as per the above instructions, then
run

`{.}
$ cd dist
$ npm link
`

If you do not wish to add \"c-slang\" to your PATH, replace \"c-slang\" with
\"node dist/repl/repl.js\" in the following examples.

To try out _Source_ in a REPL, run

`{.}
$ c-slang -c [chapter] # default: 1
`

You can set additional options:

`{.}
Usage: c-slang [PROGRAM_STRING] [OPTION]
-h, --help display this help
-e, --eval don't show REPL, only display output of evaluation
`

Currently, valid CHAPTER/VARIANT combinations are:

- --chapter=1 --variant=calc

Hint: In bash you can take the PROGRAM_STRING out of a file as follows:

`{.}
$ c-slang -n -e "$(< my_source_program.js)"
`

Documentation

Source is documented here: https://docs.sourceacademy.org/

Requirements

- bash: known working version: GNU bash, version 5.0.16
- latexmk: Version 4.52c
- pdflatex: known working versions
- pdfTeX 3.14159265-2.6-1.40.18 (TeX Live 2017)

To build the documentation, run

`{.}
$ git clone https://github.com/source-academy/c-slang.git
$ cd c-slang
$ yarn
$ yarn install
$ yarn jsdoc # to make the web pages in c-slang/docs/source
$ cd docs/specs
$ make # to make the PDF documents using LaTeX
`

Note: The documentation may not build on Windows, depending on your bash setup,
see above.

Documentation on the Source libraries are generated from inline documentation in
the library sources, a copy of which are kept in docs/lib/*.js. The command
yarn jsdoc generates the documentation and places it in the folder
docs/source. You can test the documentation using a local server:

`{.}
$ cd docs/source; python -m http.server 8000
`

Documentation of libraries is displayed in autocomplete in the frontend. This
documentation is generated by ./scripts/updateAutocompleteDocs.py and placed
in src/editors/ace/docTooltip/*.json files. This script is run by
yarn buildprior to tsc. To add a Source variant to the frontend autocomplete,
edit src/editors/ace/docTooltip/index.ts
and ./scripts/updateAutocompleteDocs.py.

Testing

js-slang comes with an extensive test suite. To run the tests after you made
your modifications, run yarn test. Regression tests are run automatically when
you want to push changes to this repository. The regression tests are generated
using jest and stored as snapshots in src/\_\_tests\_\_. After modifying
js-slang, carefully inspect any failing regression tests reported in red in
the command line. If you are convinced that the regression tests and not your
changes are at fault, you can update the regression tests as follows:

`{.}
$ yarn test -- --updateSnapshot
`

Error messages

To enable verbose messages, have the statement "enable verbose"; as the first
line of your program. This also causes the program to be run by the interpreter.

There are two main kinds of error messages: those that occur at runtime and
those that occur at parse time. The first can be found in
interpreter-errors.ts, while the second can be found in rules/.

Each error subclass will have explain() and elaborate(). Displaying the
error will always cause the first to be called; the second is only called when
verbose mode is enabled. As such, explain() should be made to return a string
containing the most basic information about what the error entails. Any
additional details about the error message, including specifics and correction
guides, should be left to elaborate().

Please remember to write test cases to reflect your added functionalities. The
god of this repository is self-professed to be very particular about test cases.

Using your xx-slang in your local Source Academy

(xx is the name of your language)

A common issue when developing modifications to js-slang is how to test it using
your own local frontend. Assume that you have built your own frontend locally,
here is how you can make it use your own xx-slang, instead of the one that the
Source Academy team has deployed to npm.

First, build and link your local xx-slang: (don't forget to modify the "c-slang" in both projects)

`{.}
$ cd xx-slang
$ yarn build
$ yarn link
`

Then, from your local copy of frontend:

`{.}
$ cd frontend
$ yarn link "xx-slang"
`

Then start the frontend and the new js-slang will be used.

Talks and Presentations

- How js-slang` works under the hood [17th Jan 2023][The
Gathering][slides]

License

All sources in this repository are licensed under the
[Apache License Version 2][apache2].

[apache2]: https://www.apache.org/licenses/LICENSE-2.0.txt