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var jaycue = require("jaycue")

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jaycue v1.2.9

jaycue mimics the best parts [jq]( in pure JavaScript.


npm version npm dependents Downloads run on

jaycue is my little side project that mimics the best parts jq in pure JavaScript. I wrote a blog post about it on

I am TDD'ing this to get some practice, using the jq documentation, and hopefully make something useful. Please see below for some similar, more mature, great projects built around jq.


$ npm install jaycue


const jq = require('jaycue');

console.log(jq({foo: 123}, '.foo'));

Supported Filters

Basic Filters

  "value": 42,
  "text": "less interesting data",
  "name": {
    "first": "Brian"
    "last": "Olore"
.{ "value": 42, "text": "less interesting data","name": { "first": "Brian" "last": "Olore" } } (object)
.value42 (number)
.textless interesting data (string)
.["text"]less interesting data (string)
.name"name": { "first": "Brian" "last": "Olore" } (object)
.name.firstBrian (string)

Array Filters

.[]"a","b","c","d","e" (not json)

Array Slicing Filters

.[2:4]["c", "d"]
.[:3]["a", "b", "c"]
.[:-3]["a", "b"]
.[-2:]["d", "e"]
.[2:]["c", "d", "e"]

Select Function

  {"id": "first", "val": 1},
  {"id": "second", "val": 2}
.[] \| select(.id == "second"){"id": "second", "val": 2}
.[] \| select(.id == "second") \| .val2 (number)
.[] \| select(.id == "second") .val2 (number)
.[] \| select(.id != "second") .val1 (number)


Must have jq installed to run tests jq is now supplied by node-jq

As previously mentioned, all code has been test-driven. The test-helper provides a way to call the actual jq, making it easy to compare results.

Running tests

npm test


Read the jq Language Description

Check out this project which is a JavaScript wrapper around jq: Here are some more cool jq projects:


  • Logo by Joseph Olore


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