Function compile_checked 

pub fn compile_checked(
    source: String,
    filename: &str,
    resolver: &ImportResolver,
) -> (CompileOutput, Vec<ExportImage>)

Compiles source the way candela build does: the whole program, and then an entry point for every fully annotated function in it.

candela check and Engine::compile are check steps for that build, so they compile through here too and refuse what the build would refuse. The export table comes back with the compile result for the caller that writes an artifact; a caller that only wanted the check drops both.