this.tag = tag || 0;
this.to_string = function () {
// append count copies of str to accum
- function markup(accum, count) {
- if (count === 0) {
- return accum;
- } else {
- return markup(accum + "'", count - 1);
- }
- }
- return markup(this.name, this.tag);
+// function markup(accum, count) {
+// if (count === 0) {
+// return accum;
+// } else {
+// return markup(accum + "'", count - 1);
+// }
+// }
+// return markup(this.name, this.tag);
+ var s = this.name;
+ for (var count = 0; count < this.tag; count += 1) {
+ s += "'";
+ }
+ return s;
};
this.equal = function (other) {
return (this.tag === other.tag) && (this.name === other.name);
};
this.eval_loop = function (stack, eta) {
function unwind(left, stack) {
- if (stack.length === 0) {
- return left;
- } else {
- var x = stack[0];
- var xs = stack.slice(1);
- return unwind(new Lambda_app(left, x.eval_loop([], eta)), xs);
- }
+// if (stack.length === 0) {
+// return left;
+// } else {
+// var x = stack[0];
+// var xs = stack.slice(1);
+// return unwind(new Lambda_app(left, x.eval_loop([], eta)), xs);
+// }
+ var res = left, x;
+ while (stack.length) {
+ x = stack.shift();
+ res = new Lambda_app(res, x.eval_loop([], eta));
+ }
+ return res;
}
return unwind(this, stack);
};
}
};
this.to_int = function (sofar) {
- if (this.body.body && this.body.body.variable && this.body.bound.equal(this.body.body.variable)) {
- return 0 + sofar;
- } else if (this.body.variable && this.bound.equal(this.body.variable)) {
- return 1 + sofar;
- } else if (this.body.body && this.body.body.left && this.body.body.left.variable && this.bound.equal(this.body.body.left.variable)) {
- var new_int = new Lambda_lam(this.bound, new Lambda_lam(this.body.bound, this.body.body.right));
- return new_int.to_int(1 + sofar);
- } else {
- return "not a church numeral";
- }
+// if (this.body.body && this.body.body.variable && this.body.bound.equal(this.body.body.variable)) {
+// return 0 + sofar;
+// } else if (this.body.variable && this.bound.equal(this.body.variable)) {
+// return 1 + sofar;
+// } else if (this.body.body && this.body.body.left && this.body.body.left.variable && this.bound.equal(this.body.body.left.variable)) {
+// var new_int = new Lambda_lam(this.bound, new Lambda_lam(this.body.bound, this.body.body.right));
+// return new_int.to_int(1 + sofar);
+// } else {
+// return "not a church numeral";
+// }
+ var res = 0, s = this.bound, z, cursor;
+ if (this.body.variable && s.equal(this.body.variable)) {
+ return 1;
+ } else if (this.body.bound) {
+ z = this.body.bound;
+ cursor = this.body.body;
+ while (cursor.left && cursor.left.variable && s.equal(cursor.left.variable)) {
+ res += 1;
+ cursor = cursor.right;
+ }
+ if (cursor.variable && z.equal(cursor.variable)) {
+ return res;
+ }
+ }
+ return "not a church numeral";
};
}