tangentstorm

# i wrote this, and it works, but then i decided to just use Godot's own Expression parser.
# https://docs.godotengine.org/en/latest/tutorials/scripting/evaluating_expressions.html

func _examples():
	test('@title["the deck"]')
	test('@show["jp-editor"; 0]')
	test('@ed.xy[  0 5]')

func test(cmd:String):
	if cmd.begins_with('@'):

tangentstorm

NB. Code from the "Basic Animation In J" video
NB. https://www.youtube.com/watch?v=uL-70fMTVnw
NB. ------------------------------------------------------------------------

NB. animation demo

load 'viewmat'
coinsert'jgl2'

wd 'pc w0 closeok'                  NB. parent control (window) named 'w0'

tangentstorm

NB. Core logic for a tiny editor in J.
NB. No select/copy/paste (in this gist), but it does support multiple cursors.
NB. This started as the code for editing a single line of text, but I'm now
NB. using three copies simultaneously: one for a single token, one for
NB. boxed tokens on a line, and one for boxed lines in a buffer.
coclass 'ed'

init =: {{
  B =: ''  NB. the buffer to edit.
  C =: 0   NB. cursor position(s)

tangentstorm

/ grammar combinators in K
/ for longer description (in python), see:
/ http://tangentstorm.github.io/draft/wejalboot.py.html


/ -- misc helper functions ------------------------------------

join:{[sep;strs] / join strs with 'sep' as delimiter
    (#sep) _ ,/ sep,' strs}

tangentstorm

clear''
NB. Parser Combinators for J
NB.
NB. The semantics here are heavily inspired by 
NB. Allesandro Warth's ometa system:
NB.
NB.   http://tinlizzie.org/ometa/
NB.
NB. but implemented as parser combinators rather than a standalone language.
NB.

tangentstorm

const DATA=0, CALL=1, WORK=2, TEMP=3

class Worker {

  vm = null   // virtual machine
  w = 0       // worker number
  f = 0       // function pointer
  e = 0       // execution pointer
  t = 0       // current token in function

tangentstorm

glue = (x,y) => x === undefined ? y : Array.isArray(x) ? x.concat(y) : [x,y]

function meld(xs) {
  let idx = {}, res = [], it
  for (x of xs) {
    if (x.id in idx) it = res[idx[x.id]]
    else { it = {id: x.id}; idx[x.id] = res.length; res.push(it) }
    for (k of Object.keys(x)) if (k!=='id') it[k] = glue(it[k], x[k]) }
  return res }

tangentstorm

   c =: '01' ([: +/ =)"0 _ ]           NB. count 0 and 1
   t =: {{(*/ <:/"1 c\ y) *. =/c y }}  NB. the two rules
   g =: {{'01' {~ #:i.2^2*y}}          NB. generate the numbers
   f =: {{y {~ I.t"1 y}}               NB. filter by t
   f g 3

tangentstorm

var b4 = (new function() { var EOF='\0',self = {

    d:[], a:[],                             // data and auxiliary/return stack
    defs:[],core:[],scope:[],               // dictionary
    base:10,                                // numbers
    cp:-1, ch:'\x01',ibuf:[],wd:'',         // lexer state
    compiling:false,state:[],target:[],     // compiler state

    def : function (k,v){
        var res=self.defs.length; self.defs.push(v); self.scope[0].push([k,res]); return res },

tangentstorm

C =: -:`(1+3&*)@.(2&|)"0
R =: -:^:(-.@(2&|))^:_
S =: 1 + 3&*
T =: R@([`S@.(2&|))"0
T i. 10