Function evaluate 

pub fn evaluate(
    file: &str,
    outputs: &[String],
    inputs: &[String],
) -> (i32, Option<String>, Vec<(String, Diag)>, Vec<String>)

decl evaluate: (exit code, the document for stdout, diagnostics tagged with the file each is reported against, bare stderr lines to print after them). What to emit, and where (§5.5): each --output name[=file] names a root — an output, or an input bound by –input or demanded through its fallback — and the file its document goes to (stdout without one); with no –output, the entry module’s exported outputs, as one object keyed by name, on stdout