kit

dangling_else.ebnf (940B)

---

 // RED FIXTURE — does not compile; preserved on purpose.
 //
 // The textbook dangling-else, written the natural way: `else` is optional and
 // binds to the nearest `if`. Every hand-written recursive-descent parser does
 // this with a greedy "if there's an else, take it" shift. LL(1) predict-set
 // analysis can't express that preference, so this is a hard conflict here — an
 // inherent LL(1) limitation, not a generator bug. (Keywords go through
 // %keywords so the conflict isn't masked by the shadowed-literal check.)
 //
 // Observed diagnostic (now a precise, in-file location pointing at `else_part?`):
 //   red/dangling_else.ebnf:19:33: error: LL(1) conflict in optional in rule
 //   stmt: token 'ELSE' can start the body or follow the optional
 %lex {
   %skip WS = [ \t\r\n]+;
   IDENT = [A-Za-z_] [A-Za-z0-9_]*;
   %keywords IDENT { IF="if"; ELSE="else"; }
 }
 
 stmt = "if" IDENT stmt else_part? | IDENT ";";
 else_part = "else" stmt;