The C++ implementation can be compiled with emscripten to produce a Javascript implementation of Jsonnet. This is how we implement our Jsonnet demo. It is not the fastest possible Javascript implementation of Jsonnet, but it is easy to build, and is sufficient for many purposes.
To compile it, first install emscripten and ensure em++ and emcc are in your path. Then make libjsonnet.js.
An unofficial nodejs package of Jsonnet is also available.
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