2014-07-10 17:04:26 -04:00

43 lines
1.2 KiB
JavaScript

(function (tree) {
tree.Condition = function (op, l, r, i, negate) {
this.op = op.trim();
this.lvalue = l;
this.rvalue = r;
this.index = i;
this.negate = negate;
};
tree.Condition.prototype.eval = function (env) {
var a = this.lvalue.eval(env),
b = this.rvalue.eval(env);
var i = this.index, result;
var result = (function (op) {
switch (op) {
case 'and':
return a && b;
case 'or':
return a || b;
default:
if (a.compare) {
result = a.compare(b);
} else if (b.compare) {
result = b.compare(a);
} else {
throw { type: "Type",
message: "Unable to perform comparison",
index: i };
}
switch (result) {
case -1: return op === '<' || op === '=<';
case 0: return op === '=' || op === '>=' || op === '=<';
case 1: return op === '>' || op === '>=';
}
}
})(this.op);
return this.negate ? !result : result;
};
})(require('../tree'));