Pounce is a small concatenative programming language. The core of the language includes a parser and an interpreter (written in TypeScript). A core dictionary of Pounce words (functions on a value stack) is included. This dictionary can be augmented or replaced with a custom, perhaps more efficient or expressive, dictionary.

Pounce follows in the footsteps of Joy, Factor, Cat and Kitten, in that it is, Concatenative and a 'stack-based' language. To summarize, Pounce has:

• code written in post-fix notation (yes it will feel backwards at first, but post-fix has advantages)
• very little syntax -- no parentheses, just 'words' or 'lists of words' separated by spaces (at first you might experience syntax withdrawal symptoms)
• no variables -- a stack is used to store values, (i.e. it's a mostly point-free, stack-based language) (see the word pounce for non-variable naming of stack elements)
• the nice property that "all words are functions!" including values (e.g the word 5) where the identity function is used.
• the same signature for all words -- they receive a stack as an argument and return a new stack
• no assignment operator and no side-effects (the program is the input and the final stack is the output)
• programs that are built up by composing words (rather than the application of functions to variable arguments), concatenative programming is essentially functional composition into a single function (or program)

To start Pounce programming in the browser, you can try this sampler. Or clone this starter project template and extend it how ever you see fit.

RunKit https://runkit.com/embed/i6tu1bf90mz6

// Run a small Pounce program that doubles 21. // When logLevel > 0, intermediate states of the stack and program are displayed.  var core = require("@pounce-lang/core") var interp = core.interpreter(core.parse("21 dup +"), {logLevel:1}); var pounceState = interp.next(); while (pounceState.value.active) { const stack = core.unParse(pounceState.value.stack); const prog = core.unParse(pounceState.value.prog); console.log(`${stack} | ${prog}`); pounceState = interp.next(); } console.log(pounceState.value.stack);

npm i npm run build 

and run the tests

npm run test