Add Extract A List Of Values as a jq til

jq/extract-a-list-of-values.md

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+# Extract A List Of Values
+
+[`jq`](https://stedolan.github.io/jq/) can be used to extract a list of values
+from an array in a JSON file.
+
+Consider the following JSON:
+
+```json
+{
+  "items": [
+    { "id": 1, "name": "Liz Lemon" },
+    { "id": 2, "name": "Pete Hornberger" },
+    { "id": 3, "name": "Tracy Jordan" },
+    { "id": 4, "name": "Jenna Maroney" }
+  ]
+}
+```
+
+First, you need to specify the selector path to the list. One it's own that
+will grab the list.
+
+```bash
+$ jq '.items' data.json
+[
+  {
+    "id": 1,
+    "name": "Liz Lemon"
+  },
+  ...
+]
+```
+
+Then you need to use brackets to interact with the list. `.items[0]` and
+`.items[1]` would grab the first and second item in the list, respectively.
+Leaving the brackets empty (`.items[]`) tells `jq` that you want to interact
+with each item in the list.
+
+Then tack on a selector for what you want out of each item.
+
+```bash
+$ jq '.items[].name' data.json
+"Liz Lemon"
+"Pete Hornberger"
+"Tracy Jordan"
+"Jenna Maroney"
+```
+
+This grabs the name from each of the objects within the _items_ array. The
+results are printed to stdout.