Lazy
The lazy setting1.47.0 causes the evaluator to skip evaluating
unused variables. This can be beneficial when a justfile contains variables
that are expensive to evaluate but only sometimes used.
In the following justfile, token will be skipped when only invoking bar:
set lazy
token := `expensive-script-to-get-credentials`
foo:
curl -H "Authorization: Bearer {{ token }}" https://example.com/foo
bar:
cargo test
Because just cannot determine when exported variables are used, assignments
with export and assignments in a module with set export will always be
evaluated.