celeref-lang

A versatile interpreter in python to execute programs written in JSON.

Installation

First you need to install python 3. Now you can install the package via pip:

$ python -m pip install --user -U celeref-lang
# In linux, you might have to use `python3` instead.
# Make sure to check `python --version` first.

Test if it is installed successfully:

$ celeref
# It should print a help message

$ celeref --version
# It should print the installed version

If it says celeref is not found, follow this help:

• Windows
• Linux
• MacOS

Writing your first program

You need a code-editor that supports intellisense for JSON schema. My preference is Visual Studio Code.

• Create a JSON file in Visual Studio Code
• Add the schema path located in src/schema folder. See examples in examples folder for help.

With schema defined, editor will catch schema errors and auto-suggest available expressions.

Here is a sample program written in celeref-lang:

{
  "$schema": "https://raw.githubusercontent.com/dipu-bd/celeref-lang/master/src/schema/schema.json",
  "name": "Hello World",
  "program": [
    {
      "state": "Hello World"
    },
    {
      "print": "state"
    }
  ]
}

Save the program to hello-world.json file, and run it using:

$ celeref hello-world.json
----------
Hello World

------ 0.000 seconds ------

Building from source

You need Python 3 to execute this script.

• Clone the repository first
• Create a new virtual environment
  • python -m venv venv
• Activate it;
  • In Windows: venv\Scripts\activate
  • In Linux: venv/bin/activate
  • In MacOS: venv/bin/activate
• Now install dependencies:
  • pip install -U wheel pip
  • pip install -r requirements.txt
• Now to run the script:
  • python src <path/to/your-source.json>

E.g. To run the hello-world.json example:

$ python src examples/hello-world.json
Hello World

Documentation

This project in under development. APIs are subjected to change in future. Documentation is further away. Follow schema descriptions for basic documentation for now.

To note a few basic things:

• state is a very important variable in this program. After executing a statement, the result is always stored in state first.

• After program has finished running the final value of state will be the result.

• To pass and array or objects as arguments to call method, you can use { "state": <your array or object> }.

• To display a list of all available functions:

$ celeref -s

• To search for specific functions, pass a query after -s:

$ celeref -s mod
----- [divmod] -----
Return the tuple (x//y, x%y).  Invariant: div*y + mod == x.

----- [math.fmod] -----
Return fmod(x, y), according to platform C.

x % y may differ.

----- [math.modf] -----
Return the fractional and integer parts of x.

Both results carry the sign of x and are floats.

----- [op.mod] -----
mod(a, b) -> number
Same as `a % b`

Find the modulus of two numbers