feat: add #identifier syntax for symbolic literals

Symbolic type existed in AST but had no parse syntax. Added #prefix
convention (e.g. #x, #pi, #alpha) matching existing 0x/0b patterns.
Grammar, parser, formatter, and pretty-printer all updated. 84 tests pass.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: hyperpolymath

crates/jtv-core/src/formatter.rs

@@ -487,7 +487,8 @@ impl Formatter {
                 self.output.push_str(s);
             }
             Number::Symbolic(s) => {
-                self.output.push_str(s);
+                // Symbolic literals use '#' prefix (e.g., #x, #pi)
+                self.output.push_str(&format!("#{}", s));
             }
         }
     }

crates/jtv-core/src/grammar.pest

@@ -118,10 +118,13 @@ number = {
     | rational
     | hex
     | binary
+    | symbolic
     | float
     | integer
 }
 
+symbolic = @{ "#" ~ (ASCII_ALPHA | "_") ~ (ASCII_ALPHANUMERIC | "_")* }
+
 integer = @{ "-"? ~ ASCII_DIGIT+ }
 float = @{ "-"? ~ ASCII_DIGIT+ ~ "." ~ ASCII_DIGIT+ ~ (("e" | "E") ~ ("+" | "-")? ~ ASCII_DIGIT+)? }
 rational = @{ integer ~ "/" ~ ASCII_NONZERO_DIGIT ~ ASCII_DIGIT* }

crates/jtv-core/src/parser.rs

@@ -422,6 +422,11 @@ fn parse_number(pair: pest::iterators::Pair<Rule>) -> Result<Number> {
         }
         Rule::hex => Ok(Number::Hex(pair.as_str().to_string())),
         Rule::binary => Ok(Number::Binary(pair.as_str().to_string())),
+        Rule::symbolic => {
+            // Strip the '#' prefix to get the symbolic name
+            let name = pair.as_str().trim_start_matches('#').to_string();
+            Ok(Number::Symbolic(name))
+        }
         _ => Err(JtvError::ParseError(format!(
             "Unknown number type: {:?}",
             pair.as_rule()
@@ -602,4 +607,30 @@ mod tests {
         let result = parse_program(code);
         assert!(result.is_ok());
     }
+
+    #[test]
+    fn test_parse_symbolic_literal() {
+        let code = "x = #pi + #e";
+        let result = parse_program(code);
+        assert!(result.is_ok(), "Failed to parse symbolic literals: {:?}", result.err());
+        let program = result.unwrap();
+        // Verify the AST contains symbolic numbers
+        if let TopLevel::Control(ControlStmt::Assignment(ref assign)) = program.statements[0] {
+            if let Expr::Data(DataExpr::Add(ref left, ref right)) = assign.value {
+                assert_eq!(**left, DataExpr::Number(Number::Symbolic("pi".to_string())));
+                assert_eq!(**right, DataExpr::Number(Number::Symbolic("e".to_string())));
+            } else {
+                panic!("Expected Add expression");
+            }
+        } else {
+            panic!("Expected assignment");
+        }
+    }
+
+    #[test]
+    fn test_parse_symbolic_with_underscore() {
+        let code = "y = #my_var";
+        let result = parse_program(code);
+        assert!(result.is_ok(), "Failed to parse symbolic with underscore: {:?}", result.err());
+    }
 }

crates/jtv-core/src/pretty.rs

@@ -417,7 +417,7 @@ impl PrettyPrinter {
             }
             Number::Hex(s) => s.clone(),
             Number::Binary(s) => s.clone(),
-            Number::Symbolic(s) => s.clone(),
+            Number::Symbolic(s) => format!("#{}", s),
         }
     }
 

shared/grammar/jtv.ebnf

@@ -109,7 +109,7 @@ function_type = "Fn" "(" [ type_annotation { "," type_annotation } ] ")" "->" ty
 return_type = type_annotation ;
 
 (* ===== LITERALS ===== *)
-number = integer | float | rational | complex | hex | binary ;
+number = integer | float | rational | complex | hex | binary | symbolic ;
 
 integer = [ "-" ] digit { digit } ;
 float = [ "-" ] digit { digit } "." digit { digit } [ exponent ] ;
@@ -118,6 +118,7 @@ rational = integer "/" integer ;
 complex = number "+" number "i" | number "i" ;
 hex = "0x" hex_digit { hex_digit } ;
 binary = "0b" ("0" | "1") { "0" | "1" } ;
+symbolic = "#" letter { letter | digit | "_" } ;  (* Symbolic math names, e.g. #x, #pi, #alpha *)
 
 list_literal = "[" [ data_expr { "," data_expr } ] "]" ;
 tuple_literal = "(" data_expr "," data_expr { "," data_expr } ")" ;