[SOLVED] How do I pass literal variable templates to jq from within Make?

Issue

I'm trying to use jq within a Makefile to generate a json file. Here is a sample Makefile

foo.json:
    jq -n --arg x "bar" '{"foo": "$$x"}' > foo.json
    @cat foo.json
    @rm foo.json

When I run this with GNU Make v4.3 and jq v1.6 I get the following

make
jq -n --arg x "bar" '{"foo": "$x"}' > foo.json
{
  "foo": "$x"
}

Notice that $x shows up literally and doesn't get interpolated by jq. How do I achieve the following...

make
jq -n --arg x "bar" '{"foo": "$x"}' > foo.json
{
  "foo": "bar"
}

Solution

You simply don't need to wrap your variable in quotes:

jq -n --arg x "bar" '{foo: $x}'

Or use string interpolation:

jq -n --arg x "bar" '{foo: "\($x)"}'

Answered By - customcommander