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dev-docs/RFCs/vNext/json-converter-keyword-handling-rfc.md

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+# RFC: Syntactic sugar for @deck.gl/json
+
+* **Authors**: Andrew Duberstein (@ajduberstein)
+* **Date**: October 10, 2019
+* **Status**: Draft
+
+
+## Overview
+
+This is a proposal for adding syntactic sugar to the @deck.gl/json expression parser which will let the user distinguish
+between the keyword `type` and a string named `type`.
+
+
+## Motivation
+
+The keyword `type` occurs as a field name in many data sets, and is also of course a Javascript keyword.
+Users may want `type` to be interpreted as one or the other but currently can't specify which.
+
+The GeoJSON standard includes type in the top-level JSON, so most GeoJSON data sets break when ingested by the deck.gl/json API.
+
+## Prior Art
+
+We should likely avoid conflicting with [JSON pointer syntax](https://www.baeldung.com/json-pointer) and JSON Paths. It seems like `_`, `__`, and `@@` would be acceptable characters. We are already using `__` in deck.gl to represent internal fields, so it seems like the least ambiguity comes from use of `@@`. 
+
+## Proposal
+
+deck.gl/json will use `@@type` to indicate the Javascript `type` keyword.
+
+Additionally, add a syntax for expressions, e.g, `@@=` prefix: `@@=[lng, lat]`, so that we didn't need to know any information about prop types to deduce which strings to parse as expressions.