diff --git a/src/parser.rs b/src/parser.rs
index d228d4c..4994d2e 100644
--- a/src/parser.rs
+++ b/src/parser.rs
@@ -13,8 +13,8 @@ use nom::{
         complete::{char, space1, usize},
         streaming::one_of,
     },
-    combinator::{opt, value, verify},
-    error::{Error, ErrorKind, ParseError},
+    combinator::{opt, value},
+    error::{Error, ParseError},
     multi::many0,
     sequence::{delimited, preceded},
 };
@@ -214,7 +214,7 @@ impl<'s> Slope<'s> {
 }
 
 /// Will return the longest valid fasteval expression
-fn expression_parser<'a, I: Input + AsRef<str> + Copy, C: Into<char> + Ord + Display>(
+fn expression_parser<I: Input + AsRef<str> + Copy, C: Into<char> + Ord + Display>(
     variables: &[C],
 ) -> impl Fn(I) -> IResult<I, Expression> {
     |input: I| {