Handling for the initial token being TOK_UNKNOWN in lx syntax #457
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My intended idea was to have all syntax errors go through the same actions driven by parser.sid. But in this case SID's generated parser bails out immediately on TOK_UNKNOWN, and we never reach an ## alt. So we never reach <make-ast>, and thus never <err-syntax> about it. That's what the assertion was about; the generated parser should never return with a NULL AST. My workaround for this is just to recreate the equivalent syntax error at the top-level, which isn't very satisfying at all. But it does what we need here. Spotted by @cinco-de-mayonnaise, thank you.
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My intended idea was to have all syntax errors go through the same actions driven by parser.sid. But in this case SID's generated parser bails out immediately on TOK_UNKNOWN, and we never reach an
##alt. So we never reach<make-ast>, and thus never<err-syntax>about it.That's what the assertion was about; the generated parser should never return with a
NULLAST.My workaround for this is just to recreate the equivalent syntax error at the top-level, which isn't very satisfying at all. But it does what we need here.
Spotted by @cinco-de-mayonnaise, thank you.
This resolves #451.