message: Use better lifetime identifiers
diff: @@ -14,7 +14,7 @@ pub enum ExprError {
  UnboundVariable(Span, String),
  }
  -impl<'a> Env<'a> {
  +impl<'parent> Env<'parent> {
  pub fn check_defs<I: IntoIterator<Item = Definition>>(
  &mut self,
  defs: I,
  