diff --git a/filter-parser/src/error.rs b/filter-parser/src/error.rs
index 8a628156a..ea95caba7 100644
--- a/filter-parser/src/error.rs
+++ b/filter-parser/src/error.rs
@@ -33,7 +33,7 @@ impl<E> NomErrorExt<E> for nom::Err<E> {
 
 /// cut a parser and map the error
 pub fn cut_with_err<'a, O>(
-    mut parser: impl FnMut(Span<'a>) -> IResult<O>,
+    mut parser: impl FnMut(Span<'a>) -> IResult<'a, O>,
     mut with: impl FnMut(Error<'a>) -> Error<'a>,
 ) -> impl FnMut(Span<'a>) -> IResult<O> {
     move |input| match parser.parse(input) {
diff --git a/filter-parser/src/lib.rs b/filter-parser/src/lib.rs
index 61801e3d4..d10136ace 100644
--- a/filter-parser/src/lib.rs
+++ b/filter-parser/src/lib.rs
@@ -170,7 +170,9 @@ impl<'a> FilterCondition<'a> {
 }
 
 /// remove OPTIONAL whitespaces before AND after the provided parser.
-fn ws<'a, O>(inner: impl FnMut(Span<'a>) -> IResult<O>) -> impl FnMut(Span<'a>) -> IResult<O> {
+fn ws<'a, O>(
+    inner: impl FnMut(Span<'a>) -> IResult<'a, O>,
+) -> impl FnMut(Span<'a>) -> IResult<'a, O> {
     delimited(multispace0, inner, multispace0)
 }