braces/brackets/parentheses validator without order checking

scopeValidator.js

var openingSymbols = ['{', '[', '('],
    closingSymbols = ['}', ']', ')'],
    counter = 0;

function scopeValidator(char) {
    if (openingSymbols.indexOf(char) != -1) counter++;
    else if (closingSymbols.indexOf(char) != -1) counter--;
}

function scopeParser(text) {
    counter = 0;
    for(var i=0; i <= text.length; i++) {
        scopeValidator(text[i]);
    }
    if(counter==0) return true;
    return false;
}

scopeParser("{ [ ] ( ) }");