introduce hir crate

crates/ra_db/src/lib.rs

@@ -13,7 +13,7 @@ mod loc2id;
 
 use std::sync::Arc;
 use ra_editor::LineIndex;
-use ra_syntax::SourceFileNode;
+use ra_syntax::{TextUnit, SourceFileNode};
 
 #[derive(Clone, Copy, Debug, PartialEq, Eq, Hash, PartialOrd, Ord)]
 pub struct Canceled;
@@ -81,3 +81,9 @@ fn file_lines(db: &impl SyntaxDatabase, file_id: FileId) -> Arc<LineIndex> {
     let text = db.file_text(file_id);
     Arc::new(LineIndex::new(&*text))
 }
+
+#[derive(Clone, Copy, Debug)]
+pub struct FilePosition {
+    pub file_id: FileId,
+    pub offset: TextUnit,
+}