First steps for the macro system

orchid-base/src/location.rs

@@ -108,6 +108,10 @@ impl SrcRange {
 	pub fn to_api(&self) -> api::SourceRange {
 		api::SourceRange { path: self.path.to_api(), range: self.range.clone() }
 	}
+	pub fn to(&self, rhs: &Self) -> Self {
+		assert_eq!(self.path, rhs.path, "Range continues across files");
+		Self { path: self.path(), range: self.start().min(rhs.start())..self.end().max(rhs.end()) }
+	}
 }
 impl From<SrcRange> for ErrPos {
 	fn from(val: SrcRange) -> Self { val.pos().into() }