Warning Numbers
You can configure which warnings the ReScript compiler generates
in the build configuration or
using the @@warning() decorator.
| # | Description |
|---|---|
| a | All flags |
| 1 | Suspicious-looking start-of-comment mark. |
| 2 | Suspicious-looking end-of-comment mark. |
| 3 | Deprecated feature. |
| 4 | Fragile pattern matching: matching that will remain complete even if additional constructors are added to one of the variant types matched. |
| 5 | Partially applied function: expression whose result has function type and is ignored. |
| 6 | Label omitted in function application. |
| 7 | Method overridden. |
| 8 | Partial match: missing cases in pattern-matching. |
| 9 | Missing fields in a record pattern. |
| 10 | Expression on the left-hand side of a sequence that doesn't have type "unit" (and that is not a function, see warning number 5). |
| 11 | Redundant case in a pattern matching (unused match case). |
| 12 | Redundant sub-pattern in a pattern-matching. |
| 13 | Instance variable overridden. |
| 14 | Illegal backslash escape in a string constant. |
| 15 | Private method made public implicitly. |
| 16 | Unerasable optional argument. |
| 17 | Undeclared virtual method. |
| 18 | Non-principal type. |
| 19 | Type without principality. |
| 20 | Unused function argument. |
| 21 | Non-returning statement. |
| 22 | Preprocessor warning. |
| 23 | Useless record "with" clause. |
| 24 | Bad module name: the source file name is not a valid OCaml module name. |
| 25 | Deprecated: now part of warning 8. |
| 26 | Suspicious unused variable: unused variable that is bound with "let" or "as", and doesn't start with an underscore ("_") character. |
| 27 | Innocuous unused variable: unused variable that is not bound with "let" nor "as", and doesn't start with an underscore ("_") character. |
| 28 | Wildcard pattern given as argument to a constant constructor. |
| 29 | Unescaped end-of-line in a string constant (non-portable code). |
| 30 | Two labels or constructors of the same name are defined in two mutually recursive types. |
| 31 | A module is linked twice in the same executable. |
| 32 | Unused value declaration. |
| 33 | Unused open statement. |
| 34 | Unused type declaration. |
| 35 | Unused for-loop index. |
| 36 | Unused ancestor variable. |
| 37 | Unused constructor. |
| 38 | Unused extension constructor. |
| 39 | Unused rec flag. |
| 40 | Constructor or label name used out of scope. |
| 41 | Ambiguous constructor or label name. |
| 42 | Disambiguated constructor or label name (compatibility warning). |
| 43 | Nonoptional label applied as optional. |
| 44 | Open statement shadows an already defined identifier. |
| 45 | Open statement shadows an already defined label or constructor. |
| 46 | Error in environment variable. |
| 47 | Illegal attribute payload. |
| 48 | Implicit elimination of optional arguments. |
| 49 | Absent cmi file when looking up module alias. |
| 50 | Unexpected documentation comment. |
| 51 | Warning on non-tail calls if @tailcall present. |
| 52 | Fragile constant pattern. |
| 53 | Attribute cannot appear in this context |
| 54 | Attribute used more than once on an expression |
| 55 | Inlining impossible |
| 56 | Unreachable case in a pattern-matching (based on type information). |
| 57 | Ambiguous or-pattern variables under guard |
| 58 | Missing cmx file |
| 59 | Assignment to non-mutable value |
| 60 | Unused module declaration |
| 61 | Unboxable type in primitive declaration |
| 62 | Type constraint on GADT type declaration |
| 101 | Unused bs attributes |
| 102 | Polymorphic comparison introduced (maybe unsafe) |
| 103 | Fragile FFI definitions |
| 104 | bs.deriving warning with customized message |
| 105 | External name is inferred from val name is unsafe from refactoring when changing value name |
| 106 | Unimplemented primitive used: |
| 107 | Integer literal exceeds the range of representable integers of type int |
| 108 | Uninterpreted delimiters (for unicode) |
| 109 | Toplevel expression has unit type |
