Returns

{String|null}:

the supplied string with delimited properties replaced with their values if all properties exist on the object, null otherwise

If remove is true, the properties found in delimiters in str are removed from data.

var string = require("can-util/js/string/string");

console.log(string.sub("foo_{bar}", {bar: "baz"}})); // -> "foo_baz"
console.log(string.sub("foo_{bar}", {})); // -> null