crates/lang/src/parser.rs

@@ -47,10 +47,10 @@ impl<'src, 'toks> Parser<'src, 'toks> {
         self.input.kind(self.pos)
     }
 
-    pub(crate) fn start(&mut self) -> Marker {
+    pub(crate) fn start(&mut self, name: &str) -> Marker {
         let pos = self.events.len();
         self.push_ev(Event::tombstone());
-        Marker::new(pos)
+        Marker::new(pos, name)
     }
 
     pub(crate) fn at(&self, kind: SyntaxKind) -> bool {
@@ -88,10 +88,10 @@ pub(crate) struct Marker {
 }
 
 impl Marker {
-    pub(crate) fn new(pos: usize) -> Self {
+    pub(crate) fn new(pos: usize, name: &str) -> Self {
         Self {
             pos,
-            bomb: DropBomb::new("Marker must be completed or abandoned"),
+            bomb: DropBomb::new(format!("Marker {name} must be completed or abandoned")),
         }
     }
 
@@ -135,7 +135,7 @@ pub(crate) struct CompletedMarker {
 
 impl CompletedMarker {
     pub(crate) fn precede(self, p: &mut Parser<'_, '_>) -> Marker {
-        let new_pos = p.start();
+        let new_pos = p.start("new_pos");
 
         match &mut p.events[self.pos] {
             Event::Start { forward_parent, .. } => {

crates/lang/src/parser/grammar.rs

@@ -5,7 +5,7 @@ use super::Parser;
 mod expression;
 
 pub fn source_file(p: &mut Parser) {
-    let root = p.start();
+    let root = p.start("root");
 
     expression::expression(p);
     p.eat_succeeding_ws();

crates/lang/src/parser/grammar/expression.rs

@@ -47,7 +47,7 @@ mod collection {
 }
 
 pub fn expression(p: &mut Parser) -> Option<CompletedMarker> {
-    let expr = p.start();
+    let expr = p.start("expr");
 
     if atom(p).or_else(|| instr(p)).is_none() {
         expr.abandon(p);

crates/lang/src/parser/grammar/expression/collection/matrix.rs

@@ -6,7 +6,7 @@ use crate::parser::{
 };
 
 pub fn matrix(p: &mut Parser) -> CompletedMarker {
-    let matrix = p.start();
+    let matrix = p.start("matrix");
     p.eat(MAT_KW);
 
     if !p.eat(PAT_DIMENSIONS) {
@@ -20,7 +20,7 @@ pub fn matrix(p: &mut Parser) -> CompletedMarker {
 }
 
 fn matrix_body(p: &mut Parser) {
-    let mat_body = p.start();
+    let mat_body = p.start("mat_body");
     if !p.eat(L_BRACK) {
         mat_body.complete_err(p, SyntaxError::Expected(vec![MAT_BODY]));
         return ();
@@ -28,10 +28,10 @@ fn matrix_body(p: &mut Parser) {
 
     let mut going = true;
 
-    let mut mat_row = p.start();
+    let mut mat_row = p.start("mat_row");
     let mut row_items = 0;
     while going {
-        let mat_item = p.start();
+        let mat_item = p.start("mat_item");
         if expression(p).is_some() {
             mat_item.complete(p, MAT_ITEM);
             row_items += 1;
@@ -39,13 +39,13 @@ fn matrix_body(p: &mut Parser) {
                 COMMA => p.do_bump(),
                 SEMICOLON => {
                     mat_row.complete(p, MAT_ROW);
-                    mat_row = p.start();
+                    mat_row = p.start("mat_row");
                     p.do_bump();
                     row_items = 0;
                 }
                 R_BRACK => going = false,
                 _ => {
-                    let err = p.start();
+                    let err = p.start("err");
                     p.do_bump();
 
                     err.complete_err(p, SyntaxError::Expected(vec![COMMA, SEMICOLON, R_BRACK]));
@@ -54,7 +54,7 @@ fn matrix_body(p: &mut Parser) {
         } else if p.at(R_BRACK) {
             going = false;
         } else {
-            let err = p.start();
+            let err = p.start("err");
             p.do_bump();
             err.complete_err(p, SyntaxError::Expected(vec![EXPR, R_BRACK]));
         }

crates/lang/src/parser/grammar/expression/instruction.rs

@@ -7,7 +7,7 @@ pub fn instr(p: &mut Parser) -> Option<CompletedMarker> {
         return None;
     }
 
-    let instr = p.start();
+    let instr = p.start("instr");
 
     instr_name(p);
     instr_params(p);
@@ -16,7 +16,7 @@ pub fn instr(p: &mut Parser) -> Option<CompletedMarker> {
 }
 
 fn instr_name(p: &mut Parser) {
-    let instr_name = p.start();
+    let instr_name = p.start("instr_name");
 
     while p.at(IDENT) {
         p.do_bump();

crates/lang/src/parser/grammar/expression/lit.rs

@@ -12,7 +12,7 @@ pub fn literal(p: &mut Parser) -> Option<CompletedMarker> {
         return None;
     }
 
-    let lit = p.start();
+    let lit = p.start("lit");
 
     p.do_bump();
 

testfiles/test.owo

@@ -1,4 +1,4 @@
 mat 2x2 [
-	1, 2;
+	1 2, 2;
 	3, 4
 ]