diff --git a/src/protocol/inputsource.rs b/src/protocol/inputsource.rs
index 106b6d76c9ac813bdc99bff0158ca7be8a3c7eec..756f51cc32c3153a8d629f85f7c3ef02942d0521 100644
--- a/src/protocol/inputsource.rs
+++ b/src/protocol/inputsource.rs
@@ -164,11 +164,6 @@ impl InputPosition {
         }
         &source.input[start..end]
     }
-    fn eval_error<S: ToString>(&self, message: S) -> EvalError {
-        EvalError { position: *self, message: message.to_string(), backtrace: Backtrace::new() }
-    }
-
-    pub(crate) fn col(&self) -> usize { self.column }
 }
 
 impl Default for InputPosition {
@@ -185,9 +180,6 @@ impl fmt::Display for InputPosition {
 
 pub trait SyntaxElement {
     fn position(&self) -> InputPosition;
-    fn error<S: ToString>(&self, message: S) -> EvalError {
-        self.position().eval_error(message)
-    }
 }
 
 #[derive(Debug)]
@@ -315,172 +307,3 @@ impl ParseError {
         self.with_postfixed(ParseErrorType::Info, source, position, msg)
     }
 }
-
-#[derive(Debug, Clone)]
-pub struct EvalError {
-    position: InputPosition,
-    message: String,
-    backtrace: Backtrace,
-}
-
-impl EvalError {
-    pub fn new<S: ToString>(position: InputPosition, message: S) -> EvalError {
-        EvalError { position, message: message.to_string(), backtrace: Backtrace::new() }
-    }
-    // Diagnostic methods
-    pub fn write<A: io::Write>(&self, source: &InputSource, writer: &mut A) -> io::Result<()> {
-        if !source.filename.is_empty() {
-            writeln!(
-                writer,
-                "Evaluation error at {}:{}: {}",
-                source.filename, self.position, self.message
-            )?;
-        } else {
-            writeln!(writer, "Evaluation error at {}: {}", self.position, self.message)?;
-        }
-        let line = self.position.context(source);
-        writeln!(writer, "{}", String::from_utf8_lossy(line))?;
-        let mut arrow: Vec<u8> = Vec::new();
-        for pos in 1..self.position.column {
-            let c = line[pos - 1];
-            if c == b'\t' {
-                arrow.push(b'\t')
-            } else {
-                arrow.push(b' ')
-            }
-        }
-        arrow.push(b'^');
-        writeln!(writer, "{}", String::from_utf8_lossy(&arrow))
-    }
-    pub fn print(&self, source: &InputSource) {
-        self.write(source, &mut std::io::stdout()).unwrap()
-    }
-    pub fn display<'a>(&'a self, source: &'a InputSource) -> DisplayEvalError<'a> {
-        DisplayEvalError::new(self, source)
-    }
-}
-
-impl From<EvalError> for io::Error {
-    fn from(_: EvalError) -> io::Error {
-        io::Error::new(io::ErrorKind::InvalidInput, "eval error")
-    }
-}
-
-#[derive(Clone, Copy)]
-pub struct DisplayEvalError<'a> {
-    error: &'a EvalError,
-    source: &'a InputSource,
-}
-
-impl DisplayEvalError<'_> {
-    fn new<'a>(error: &'a EvalError, source: &'a InputSource) -> DisplayEvalError<'a> {
-        DisplayEvalError { error, source }
-    }
-}
-
-impl fmt::Display for DisplayEvalError<'_> {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        let mut vec: Vec<u8> = Vec::new();
-        match self.error.write(self.source, &mut vec) {
-            Err(_) => {
-                return fmt::Result::Err(fmt::Error);
-            }
-            Ok(_) => {}
-        }
-        write!(f, "{}", String::from_utf8_lossy(&vec))
-    }
-}
-
-// #[cfg(test)]
-// mod tests {
-//     use super::*;
-
-//     #[test]
-//     fn test_from_string() {
-//         let mut is = InputSource::from_string("#version 100\n").unwrap();
-//         assert!(is.input.len() == 13);
-//         assert!(is.line == 1);
-//         assert!(is.column == 1);
-//         assert!(is.offset == 0);
-//         let ps = is.pos();
-//         assert!(ps.line == 1);
-//         assert!(ps.column == 1);
-//         assert!(ps.offset == 0);
-//         assert!(is.next() == Some(b'#'));
-//         is.consume();
-//         assert!(is.next() == Some(b'v'));
-//         assert!(is.lookahead(1) == Some(b'e'));
-//         is.consume();
-//         assert!(is.next() == Some(b'e'));
-//         is.consume();
-//         assert!(is.next() == Some(b'r'));
-//         is.consume();
-//         assert!(is.next() == Some(b's'));
-//         is.consume();
-//         assert!(is.next() == Some(b'i'));
-//         is.consume();
-//         {
-//             let ps = is.pos();
-//             assert_eq!(b"#version 100", ps.context(&is));
-//             let er = is.error("hello world!");
-//             let mut vec: Vec<u8> = Vec::new();
-//             er.write(&is, &mut vec).unwrap();
-//             assert_eq!(
-//                 "Parse error at 1:7: hello world!\n#version 100\n      ^\n",
-//                 String::from_utf8_lossy(&vec)
-//             );
-//         }
-//         assert!(is.next() == Some(b'o'));
-//         is.consume();
-//         assert!(is.next() == Some(b'n'));
-//         is.consume();
-//         assert!(is.input.len() == 13);
-//         assert!(is.line == 1);
-//         assert!(is.column == 9);
-//         assert!(is.offset == 8);
-//         assert!(is.next() == Some(b' '));
-//         is.consume();
-//         assert!(is.next() == Some(b'1'));
-//         is.consume();
-//         assert!(is.next() == Some(b'0'));
-//         is.consume();
-//         assert!(is.next() == Some(b'0'));
-//         is.consume();
-//         assert!(is.input.len() == 13);
-//         assert!(is.line == 1);
-//         assert!(is.column == 13);
-//         assert!(is.offset == 12);
-//         assert!(is.next() == Some(b'\n'));
-//         is.consume();
-//         assert!(is.input.len() == 13);
-//         assert!(is.line == 2);
-//         assert!(is.column == 1);
-//         assert!(is.offset == 13);
-//         {
-//             let ps = is.pos();
-//             assert_eq!(b"", ps.context(&is));
-//         }
-//         assert!(is.next() == None);
-//         is.consume();
-//         assert!(is.next() == None);
-//     }
-
-//     #[test]
-//     fn test_split() {
-//         let mut is = InputSource::from_string("#version 100\n").unwrap();
-//         let backup = is.clone();
-//         assert!(is.next() == Some(b'#'));
-//         is.consume();
-//         assert!(is.next() == Some(b'v'));
-//         is.consume();
-//         assert!(is.next() == Some(b'e'));
-//         is.consume();
-//         is = backup;
-//         assert!(is.next() == Some(b'#'));
-//         is.consume();
-//         assert!(is.next() == Some(b'v'));
-//         is.consume();
-//         assert!(is.next() == Some(b'e'));
-//         is.consume();
-//     }
-// }