Passing Arrays or Objects to Helpers

In addition to passing strings, numbers, and boolean values, could it be possible to pass arrays or objects to helpers? For example:
```handlebars
{{helper_function "abc" 10 ["a","b","c"] ["d","e","f"] {"a":1,"b":2,"c":3} true}}
```

The issue gives a Handlebars example but names no files or tests. Begin by locating helper argument parsing and the existing tests for scalar arguments; done means arrays and objects can be passed alongside strings, numbers, and booleans as shown.

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