diff --git a/src/rstd/inlining.rs b/src/rstd/inlining.rs
index dc05ff9..eb7f5cc 100644
--- a/src/rstd/inlining.rs
+++ b/src/rstd/inlining.rs
@@ -88,8 +88,10 @@ impl<'a: 'c, 'c, Ctx: Context<'a>> InCtx<'a, Ctx> for &'c mut dyn DeCtx<'a, Ctx>
     }
 }
 
+pub type ResultDyn<A, I> = Result<(A, I), Vec<u8>>;
+
 pub trait InliningDyn<'c>: 'c {
-    fn idread_n(self, n: usize) -> Result<(Vec<u8>, Box<dyn InliningDyn<'c>>), Vec<u8>>;
+    fn idread_n(self, n: usize) -> ResultDyn<Vec<u8>, Box<dyn InliningDyn<'c>>>;
 
     fn idread_all(self) -> Vec<u8>;
 
@@ -97,7 +99,7 @@ pub trait InliningDyn<'c>: 'c {
 }
 
 impl<'c, I: 'c + Inlining> InliningDyn<'c> for I {
-    fn idread_n(self, n: usize) -> Result<(Vec<u8>, Box<dyn InliningDyn<'c>>), Vec<u8>> {
+    fn idread_n(self, n: usize) -> ResultDyn<Vec<u8>, Box<dyn InliningDyn<'c>>> {
         let (vec, i) = self.iread_n(n, |slice| Vec::from(slice), |slice| Vec::from(slice))?;
         Ok((vec, Box::new(i)))
     }
@@ -112,13 +114,13 @@ impl<'c, I: 'c + Inlining> InliningDyn<'c> for I {
 }
 
 pub trait InCtxDyn<'a: 'c, 'c, Ctx: Context<'a>>: InliningDyn<'c> {
-    fn icdnext_address(self) -> Result<(Address, Box<dyn InCtxDyn<'a, 'c, Ctx>>), Vec<u8>>;
+    fn icdnext_address(self) -> ResultDyn<Address, Box<dyn InCtxDyn<'a, 'c, Ctx>>>;
 
     fn idresolver(&self) -> Rc<dyn Resolver<'a, Ctx>>;
 }
 
 impl<'a: 'c, 'c, Ctx: Context<'a>, I: 'c + InCtx<'a, Ctx>> InCtxDyn<'a, 'c, Ctx> for I {
-    fn icdnext_address(self) -> Result<(Address, Box<dyn InCtxDyn<'a, 'c, Ctx>>), Vec<u8>> {
+    fn icdnext_address(self) -> ResultDyn<Address, Box<dyn InCtxDyn<'a, 'c, Ctx>>> {
         let (address, i) = self.icnext_address(|slice| Vec::from(slice))?;
         Ok((address, Box::new(i)))
     }