Katana is a newly-designed light-weight programming language and also a tree data structure expression. It aims to keep the parser simple, and highly inspired S-Expression, M-Expression and JSON format.

The parser, encoder and runner in this repository is still in early development and not ready for use.

The language itself is look like this, somewhat looks like a mixture of LISP and JavaScript:

$(
  function(factorial, (x), $(
    =(c, 1),
    =(y, 1),
    while(<=(@(c), @(x)), $(
      =(y, *(@(y), @(c))),
      =(c, +(@(c), 1))
    )),
    return(@(y))
  )),
  print(Please enter the number),
  readNumber(number),
  =(number, 10),
  =(result, factorial(@(number))),
  print(format(factorial of %d: %d, @(number), @(result)))
)

This expression can be used to represent a tree structure too:

root(
  child(
    another child,
    hello!
  ),
  3.1415,
  false,
  nil
)

MIT