{ var TOKEN = {
LITERAL:1,
OPERATOR:2,
COMPARE:3,
LOGICAL:4,
ASSIGN:5
}
function TRUE(n) {
return n===0 || !!n;
}
function OP(c,h,t,opc,valc) {
if (!t.length) return h;
opc = opc || 1;
valc = valc || 3;
var ret = [c,h];
t.forEach(function(n) {
ret.push(n[opc]);
ret.push(n[valc]);
})
return ret;
}
function EVAL(nodes,ctx) {
function E(n) {
return EVAL(nodes[n],ctx);
}
if (!Array.isArray(nodes)) console.log(nodes);
var tok = nodes[0];
switch (tok) {
case TOKEN.LITERAL:
return nodes[1];
case TOKEN.COMPARE:
var cur = EVAL(nodes[1],ctx);
var i = 2;
while (i<nodes.length) {
var op = nodes[i++];
var val = EVAL(nodes[i++],ctx);
console.log(cur,op,val);
switch (op) {
case '<': if(!(cur<val)) return false; break;
case '>': if(!(cur>val)) return false; break;
case '<=': if(!(cur<=val)) return false; break;
case '>=': if(!(cur>=val)) return false; break;
case '!=': if(!(cur!==val)) return false; break;
case '==': if(!(cur===val)) return false; break;
}
cur = val;
}
return true;
case TOKEN.LOGICAL:
var acc = EVAL(nodes[1],ctx);
var i = 2;
while (i<nodes.length) {
var op = nodes[i++];
//var val = EVAL(nodes[i++],ctx);
switch (op) {
case '&&': if (!TRUE(acc)) return false; acc=EVAL(nodes[i++],ctx); break;
case '||': if (TRUE(acc)) return acc; acc=EVAL(nodes[i++],ctx); break;
}
}
return acc;
case TOKEN.OPERATOR:
var acc = EVAL(nodes[1],ctx);
var i = 2;
while (i<nodes.length) {
var op = nodes[i++];
var val = EVAL(nodes[i++],ctx);
switch (op) {
case '+': acc+=val; break;
case '-': acc-=val; break;
case '*': acc*=val; break;
case '/': acc/=val; break;
case '%': acc%=val; break;
case ';':
case ',': acc=val; break;
}
}
return acc;
}
return "BAD TOKEN"
}
} program = e:statements { return [EVAL(e,{a:3}),e];} statements = h:statement t:(_ ';' _ statement)* ';'? { return OP('O',h,t)} statement = assign/expr assign = n:ident _ "=" _ e:expr { return ['A',n,e] } expr = or or = h:and t:( _ ("||") _ and)* { return OP(TOKEN.LOGICAL,h,t)} and = h:compare t:( _ ("&&") _ compare)* { return OP(TOKEN.LOGICAL,h,t)} compare = h:addsub t:( _ ("!="/"=="/"<="/">="/">"/"<") _ addsub)* { return OP(TOKEN.COMPARE,h,t)} addsub = h:muldiv t:( _ [+-] _ muldiv)* { return OP(TOKEN.OPERATOR,h,t)} muldiv = h:atom t:( _ [*/%] _ atom)* { return OP(TOKEN.OPERATOR,h,t)} atom = literal/path/brackets brackets = _ "(" _ e:expr _ ")" _ { return e} path = h:head t:( _ [.] _ key)* { return OP('P',h,t)} head = i:ident { return [i,'$']; }/brackets key = ident/digits/brackets
literal = boolean/number boolean = "true" eow { return [TOKEN.LITERAL,true]; } / "false" eow { return [TOKEN.LITERAL,false] } number = n:$( d:digits ('.' digits)? ([Ee] digits)?) { return [TOKEN.LITERAL,Number(n)]} digits = [0-9]+ ident = $([A-Z_]i [A-Z0-9_]i*) eow = ![a-z0-9i] _ = [ \n\r\t]* __ = [ \n\r\t]+
