variable substitution

[danielb2]

SERVICES := "nfs postfix docker"

test:
  for i in {{SERVICES}}; do echo $i; done
  for i in $SERVICES; do echo $i; done
  for i in {{SERVICES}}; do echo {{i}}; done

The first line passes, but second two fail. So what's the logic between {{ and $ here?

[casey]

In this case, SERVICES is a just variable, and i is a shell variable. You can export just variables to the shell with the export keyword, which will make the second line pass:

export SERVICES := "nfs postfix docker"

test:
  for i in {{SERVICES}}; do echo $i; done
  for i in $SERVICES; do echo $i; done

You can also import shell variables and use them in just expressions with the env_var function:

x := env_var("FOO")

bar:
  echo {{x}}

[danielb2]

Thank you 🥰