[apps-discuss] RFC 6570: what is the dot for in section 3?

Francis Galiegue <fgaliegue@gmail.com> Fri, 15 March 2013 13:24 UTC

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Date: Fri, 15 Mar 2013 14:23:59 +0100
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From: Francis Galiegue <fgaliegue@gmail.com>
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Subject: [apps-discuss] RFC 6570: what is the dot for in section 3?
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The grammar for a variable name reads as such:

     varspec       =  varname [ modifier-level4 ]
     varname       =  varchar *( ["."] varchar )
     varchar       =  ALPHA / DIGIT / "_" / pct-encoded

I fail to see any mention of the dot anywhere else in the document
when it appears in this context and I don't see any example either,
not even in appendix A. And the "varchar" grammar token adds to the
confusion since it seems to indicate the dot has a special role.

If, for example I have a variable foo defined as:

{ "bar": 1, "baz": 2 }

what is "foo.bar"? Does it refer to another variable entirely, or is
it value of key "bar" in associate array "foo"?

Francis Galiegue, fgaliegue@gmail.com
JSON Schema in Java: http://json-schema-validator.herokuapp.com