1 files changed, 38 insertions, 0 deletions
diff --git a/users/tazjin/rlox/src/treewalk/errors.rs b/users/tazjin/rlox/src/treewalk/errors.rs
new file mode 100644
index 0000000000..3d5c28f9f3
--- /dev/null
+++ b/users/tazjin/rlox/src/treewalk/errors.rs
@@ -0,0 +1,38 @@
+use crate::treewalk::interpreter::Value;
+
+#[derive(Debug)]
+pub enum ErrorKind {
+    UnexpectedChar(char),
+    UnterminatedString,
+    UnmatchedParens,
+    ExpectedExpression(String),
+    ExpectedSemicolon,
+    ExpectedClosingBrace,
+    ExpectedToken(&'static str),
+    TypeError(String),
+    UndefinedVariable(String),
+    InternalError(String),
+    InvalidAssignmentTarget(String),
+    RuntimeError(String),
+    StaticError(String),
+
+    // This variant is not an error, rather it is used for
+    // short-circuiting out of a function body that hits a `return`
+    // statement.
+    //
+    // It's implemented this way because in the original book the
+    // author uses exceptions for control flow, and this is the
+    // closest equivalent that I had available without diverging too
+    // much.
+    FunctionReturn(Value),
+}
+
+#[derive(Debug)]
+pub struct Error {
+    pub line: usize,
+    pub kind: ErrorKind,
+}
+
+pub fn report(err: &Error) {
+    eprintln!("[line {}] Error: {:?}", err.line, err.kind);
+}