Add Location (#88)

include/Basic/SourceCode.h

@@ -22,6 +22,24 @@ struct LocalSourceRange {
     constexpr bool intersects(const LocalSourceRange& other) const {
         return begin <= other.end && end >= other.begin;
     }
+
+    constexpr bool valid() const {
+        return begin != -1 && end != -1;
+    }
+};
+
+struct Location {
+    /// The file path.
+    std::string file;
+
+    /// The range in the file.
+    LocalSourceRange range;
+
+    constexpr bool operator== (const Location& other) const = default;
+
+    constexpr bool valid() const {
+        return !file.empty() && range.valid();
+    }
 };
 
 /// Get the content of the file with the given file ID.

include/Compiler/AST.h

@@ -124,6 +124,14 @@ public:
     /// files, we cut off the range at the end of the first file.
     std::pair<clang::FileID, LocalSourceRange> toLocalRange(clang::SourceRange range);
 
+    Location toLocation(clang::SourceRange range) {
+        auto [fid, localRange] = toLocalRange(range);
+        return Location{
+            .file = getFilePath(fid).str(),
+            .range = localRange,
+        };
+    }
+
 private:
     /// The interested file ID.
     clang::FileID interested;
@@ -150,7 +158,7 @@ private:
 
     /// Cache for file path. It is used to avoid multiple file path lookup.
     llvm::DenseMap<clang::FileID, llvm::StringRef> pathCache;
-    
+
     llvm::BumpPtrAllocator pathStorage;
 };