Exploring ES2018 and ES2019
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20. JSON superset

This chapter covers the ES2019 feature “JSON superset” by Richard Gibson) is at [stage 4](http://exploringjs.com/es2016-es2017/ch_tc39-process.html.

At the moment, JSON (as standardized via ECMA-404) is not a subset of ECMAScript:

Given that the syntax of JSON is fixed, a decision was made to remove the restriction for ECMAScript string literals. That simplifies the grammar of the specification, because you don’t need separate rules for ECMAScript string literals and JSON string literals.