Error Messages¶

oogac produces caveman-flavored diagnostic messages. All errors are printed to stderr; the compiler exits with code 1 when errors are found.

Error categories¶

Lex errors¶

Occur when the source contains a character or token that the lexer cannot recognise.

Format:

UGH! ME NO UNDERSTAND '<token>' at line N, col C. <hint>

Trigger	Message
Unrecognised character	`CAVE DRAWING NOT RECOGNISED. MAYBE YOU DROP CHISEL?`
Unterminated string	`CAVE SPEAK NEVER END. PUT CLOSING " ROCK.`
Escape at end of input	`ESCAPE AT END OF CAVE WALL. ADD MORE CHISELING.`

Example:

UGH! ME NO UNDERSTAND '@' at line 4, col 7. CAVE DRAWING NOT RECOGNISED. MAYBE YOU DROP CHISEL?

Parse errors¶

Occur when the token sequence does not match the grammar.

Format:

BONK! BAD GRAMMAR at line N, col C: <description>

Trigger	Message
Missing `UGHA`	`CAVE EXPECTED UGHA BUT FOUND <token>. GRAMMAR ROCK BROKEN.`
`UGGA` not followed by `WHILE`/`DO`	`UGGA NEEDS WHILE OR DO AFTER IT. FOUND <token> INSTEAD.`
Missing newline after statement	`CAVE EXPECTED LINE BREAK BUT GOT <token>. ONE THING PER ROCK SLAB.`
Unexpected token in expression	`EXPECTED EXPRESSION BUT GOT <token>. CAVE BRAIN HURT.`

Example:

BONK! BAD GRAMMAR at line 8, col 1: CAVE EXPECTED UGHA BUT FOUND Eof. GRAMMAR ROCK BROKEN.

Semantic errors¶

Occur after a successful parse, when the program is structurally valid but logically incorrect.

Format:

OW! CAVE THINKER CONFUSED at line N, col C: <description>

Trigger	Message
Undeclared variable reference	`NAME "x" NOT KNOWN. CAVE CREATURE NOT DECLARE IT WITH OOGA FIRST.`
Undeclared assignment target	`NAME "x" NOT KNOWN. CAVE CREATURE NOT DECLARE IT WITH OOGA FIRST.`
`HEAR` with undeclared variable	`HEAR NEEDS DECLARED VARIABLE BUT "x" NOT KNOWN. USE OOGA FIRST.`
`GIVEBACK` outside function	`GIVEBACK OUTSIDE FUNCTION. ONLY USE GIVEBACK INSIDE MAGIC BLOCK.`
`STOP` outside loop	`STOP OUTSIDE LOOP. CAVE BRAIN CONFUSED.`
`SKIP` outside loop	`SKIP OUTSIDE LOOP. CAVE BRAIN CONFUSED.`
Unknown function call	`FUNCTION "f" NOT KNOWN. DEFINE WITH MAGIC FIRST.`
Duplicate parameter name	`FUNCTION "f" HAS DUPLICATE PARAMETER "x". CAVE NO LIKE TWINS.`

Example:

OW! CAVE THINKER CONFUSED at line 3, col 5:
NAME "total" NOT KNOWN. CAVE CREATURE NOT DECLARE IT WITH OOGA FIRST.

Multiple errors¶

Semantic analysis collects all errors before reporting them, so you see every problem in a single compiler run instead of fixing one error at a time.

Exit codes¶

Code	Meaning
`0`	Success
`1`	Compile error or runtime failure