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Severity: error
Category: parser
Stage: Stage 1

Description

The parser entered phrase-mode error recovery three times on the same top-level item (statement, declaration, or expression) without successfully parsing the item to completion. After three consecutive phrase-recovery failures the parser considers the item unrecoverable and abandons further recovery for it.

When SJS-P099 is emitted:

  1. The per-item phrase-recovery counter has reached 3.
  2. Phrase mode is disabled for the remainder of the current item.
  3. The parser escalates immediately to panic mode at the item boundary — it discards tokens until it reaches a synchronisation token for the enclosing <Statement> or <Program> production (see specs/parser-recovery.md §Synchronisation Sets).
  4. Parsing resumes at the next top-level item. Diagnostics from subsequent items are reported normally; only the single bad item is abandoned.

This threshold prevents the parser from emitting an unbounded cascade of phantom error messages for a single malformed item. In practice the three-failure limit means SJS always reports at least a few useful diagnostics per item before giving up.

See specs/parser-recovery.md §Phrase-Mode Recovery for the authoritative algorithm.

Example

// ✗ A heavily malformed statement triggers SJS-P099
function foo() {
  const result = bar(1, (2 + ### * 4), 5)
  //                       ^^^ — phrase recovery 1: SJS-P001 (unexpected '###')
  //                           ^ — phrase recovery 2: SJS-P001 (unexpected '*'; expected ')')
  //                              ^ — phrase recovery 3: SJS-P001 (unexpected ')'; expected ')')
  //                                 — SJS-P099: recovery abandoned; skipping to next statement
}

The diagnostics emitted for the example above (in order):

SJS-P001  error  2:17  Unexpected token '###'; expected expression
SJS-P001  error  2:18  Unexpected token '*'; expected ')'
SJS-P001  error  2:22  Unexpected token ')'; expected ')'
SJS-P099  error  2:3   Too many parse errors; recovery abandoned for this item

After SJS-P099 the parser resumes at } (the sync token for <Statement> / <FunctionDecl> body) and continues parsing the rest of foo's body — or, if foo itself is abandoned, the top-level program.

Fix

Correct the underlying syntax errors that triggered the three phrase-recovery attempts. Typically this means:

  1. Read the first SJS-P001 (or more specific code) reported for the item — it usually points directly at the root cause.
  2. Fix that error, then recompile. Subsequent phantom errors usually disappear once the first is resolved.
// ✓ correct — bad token removed; expression is now valid
function foo() {
  const result = bar(1, (2 + 3) * 4, 5)
}

Notes

  • SJS-P099 is never emitted for a well-formed file; it only appears when there are already three preceding SJS-P00x diagnostics for the same item.
  • The item boundary at which escalation occurs is always the smallest enclosing top-level construct: a <Statement> inside a function body, or a <Declaration> at the module level. The parser never abandons recovery above the <Program> level.
  • The per-item phrase-recovery counter is reset for each new top-level item, so a file with multiple badly-formed items may emit SJS-P099 more than once.

Related codes

  • SJS-P001 — unexpected token (the diagnostic that increments the phrase-recovery counter)
  • SJS-P002 — unexpected end of file
  • SJS-P003 — invalid syntax in type annotation
  • SJS-P004 — invalid sum type declaration
  • SJS-P005 — invalid match expression
Documentation