diff --git a/Cargo.toml b/Cargo.toml
index 3836644..0ebe9e6 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -68,7 +68,7 @@ copy_iterator = "warn"
 default_trait_access = "warn"
 doc_link_with_quotes = "warn"
 doc_markdown = "warn"
-empty_enum = "warn"
+empty_enums = "warn"
 enum_glob_use = "allow"
 expl_impl_clone_on_copy = "warn"
 explicit_deref_methods = "warn"
@@ -152,7 +152,7 @@ struct_field_names = "warn"
 too_many_lines = "allow"
 transmute_ptr_to_ptr = "warn"
 trivially_copy_pass_by_ref = "warn"
-unchecked_duration_subtraction = "warn"
+unchecked_time_subtraction = "warn"
 unicode_not_nfc = "warn"
 unnecessary_box_returns = "warn"
 unnecessary_join = "warn"
diff --git a/src/lexer.rs b/src/lexer.rs
index fef1892..9fe6560 100644
--- a/src/lexer.rs
+++ b/src/lexer.rs
@@ -20,6 +20,9 @@ pub enum Token<'src> {
 
     // Control symbols
     Arrow,
+    /// Represents a contiguous `::` token.
+    /// This prevents the lexer from allowing spaces between colons (e.g., `use a: :b`),
+    DoubleColon,
     Colon,
     Semi,
     Comma,
@@ -71,6 +74,7 @@ impl<'src> fmt::Display for Token<'src> {
             Token::Match => write!(f, "match"),
 
             Token::Arrow => write!(f, "->"),
+            Token::DoubleColon => write!(f, "::"),
             Token::Colon => write!(f, ":"),
             Token::Semi => write!(f, ";"),
             Token::Comma => write!(f, ","),
@@ -145,16 +149,22 @@ pub fn lexer<'src>(
         _ => Token::Ident(s),
     });
 
-    let jet = just("jet::")
-        .labelled("jet")
+    let jet = just("jet")
+        .padded()
+        .ignore_then(just("::"))
+        .padded()
         .ignore_then(text::ident())
         .map(Token::Jet);
-    let witness = just("witness::")
-        .labelled("witness")
+    let witness = just("witness")
+        .padded()
+        .ignore_then(just("::"))
+        .padded()
         .ignore_then(text::ident())
         .map(Token::Witness);
-    let param = just("param::")
-        .labelled("param")
+    let param = just("param")
+        .padded()
+        .ignore_then(just("::"))
+        .padded()
         .ignore_then(text::ident())
         .map(Token::Param);
 
@@ -162,6 +172,7 @@ pub fn lexer<'src>(
         just("->").to(Token::Arrow),
         just("=>").to(Token::FatArrow),
         just("=").to(Token::Eq),
+        just("::").to(Token::DoubleColon),
         just(":").to(Token::Colon),
         just(";").to(Token::Semi),
         just(",").to(Token::Comma),
diff --git a/src/parse.rs b/src/parse.rs
index c42c6f3..909de38 100644
--- a/src/parse.rs
+++ b/src/parse.rs
@@ -1347,16 +1347,14 @@ impl ChumskyParse for CallName {
     where
         I: ValueInput<'tokens, Token = Token<'src>, Span = Span>,
     {
-        let double_colon = just(Token::Colon).then(just(Token::Colon)).labelled("::");
-
-        let turbofish_start = double_colon.clone().then(just(Token::LAngle)).ignored();
+        let turbofish_start = just(Token::DoubleColon).then(just(Token::LAngle)).ignored();
 
         let generics_close = just(Token::RAngle);
 
         let type_cast = just(Token::LAngle)
             .ignore_then(AliasedType::parser())
             .then_ignore(generics_close.clone())
-            .then_ignore(just(Token::Colon).then(just(Token::Colon)))
+            .then_ignore(just(Token::DoubleColon))
             .then_ignore(just(Token::Ident("into")))
             .map(CallName::TypeCast);
 
@@ -2163,3 +2161,28 @@ impl crate::ArbitraryRec for Match {
         })
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_double_colon() {
+        let input = "fn main() { let ab: u8 = <(u4, u4)> : :into((0b1011, 0b1101)); }";
+        let mut error_handler = ErrorCollector::new(Arc::from(input));
+        let parse_program = Program::parse_from_str_with_errors(input, &mut error_handler);
+
+        assert!(parse_program.is_none());
+        assert!(ErrorCollector::to_string(&error_handler).contains("Expected '::', found ':'"));
+    }
+
+    #[test]
+    fn test_double_double_colon() {
+        let input = "fn main() { let pk: Pubkey = witnes::::PK; }";
+        let mut error_handler = ErrorCollector::new(Arc::from(input));
+        let parse_program = Program::parse_from_str_with_errors(input, &mut error_handler);
+
+        assert!(parse_program.is_none());
+        assert!(ErrorCollector::to_string(&error_handler).contains("Expected ';', found '::'"));
+    }
+}