diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/citation/book.ml | 116 | ||||
| -rw-r--r-- | lib/citation/parse.ml | 54 | ||||
| -rw-r--r-- | lib/kernel/layer.ml | 4 | ||||
| -rw-r--r-- | lib/kernel/overlay.ml | 22 | ||||
| -rw-r--r-- | lib/kernel/overlay_ini.ml | 13 | ||||
| -rw-r--r-- | lib/kernel/sexp_error.ml | 177 | ||||
| -rw-r--r-- | lib/kernel/sexp_error.mli | 4 |
7 files changed, 317 insertions, 73 deletions
diff --git a/lib/citation/book.ml b/lib/citation/book.ml index 2a2b9c0..986a898 100644 --- a/lib/citation/book.ml +++ b/lib/citation/book.ml @@ -12,57 +12,57 @@ let to_string t = t the lectionary and was the source of every token missed in the first pass. *) let table = - [ ("genesis", [ "Gen" ]); - ("exodus", [ "Ex"; "Exod" ]); - ("leviticus", [ "Lev" ]); - ("numbers", [ "Num" ]); - ("kings_3", [ "3 Kings"; "3 Kgs." ]); - ("kings_4", [ "4 Kings" ]); - ("esdras_2", [ "2 Esd." ]); - ("tobit", [ "Tob" ]); - ("judith", [ "Judith" ]); - ("esther", [ "Esther" ]); - ("proverbs", [ "Prov" ]); - ("song_of_songs", [ "Song" ]); - ("wisdom", [ "Wis"; "Wis." ]); - ("ecclesiasticus", [ "Ecclus"; "Sir"; "Eccli" ]); - ("isaiah", [ "Isa"; "Isa." ]); - ("jeremiah", [ "Jer" ]); - ("ezekiel", [ "Ezech"; "Ezek" ]); - ("daniel", [ "Dan" ]); - ("osee", [ "Osee" ]); - ("joel", [ "Joel" ]); - ("jonas", [ "Jonas" ]); - ("malachi", [ "Mal" ]); - ("matthew", [ "Matt"; "Matt." ]); - ("mark", [ "Mark" ]); - ("luke", [ "Luke" ]); - ("john", [ "John" ]); - ("acts", [ "Acts" ]); - ("romans", [ "Rom" ]); - ("corinthians_1", [ "1 Cor"; "1 Cor." ]); - ("corinthians_2", [ "2 Cor"; "2 Cor." ]); - ("galatians", [ "Gal" ]); - ("ephesians", [ "Eph"; "Eph." ]); - ("philippians", [ "Phil" ]); - ("colossians", [ "Col"; "Col." ]); - ("thessalonians_1", [ "1 Thess"; "1 Thess." ]); - ("thessalonians_2", [ "2 Thess" ]); - ("timothy_1", [ "1 Tim." ]); - ("timothy_2", [ "2 Tim"; "2 Tim." ]); - ("titus", [ "Titus" ]); - ("hebrews", [ "Heb" ]); - ("james", [ "Jas"; "James" ]); - ("peter_1", [ "1 Pet"; "1 Pet." ]); - ("peter_2", [ "2 Pet." ]); - ("john_1", [ "1 John" ]); + [ ("genesis", [ "Gen"; "Liber Genesis"; "Genesis" ]); + ("exodus", [ "Ex"; "Exod"; "Liber Exodi"; "Exodus" ]); + ("leviticus", [ "Lev"; "Levit"; "Liber Levitici"; "Leviticus" ]); + ("numbers", [ "Num"; "Liber Numeri"; "Numbers" ]); + ("kings_3", [ "3 Kings"; "3 Kgs."; "3 Reg"; "Liber Regum III" ]); + ("kings_4", [ "4 Kings"; "4 Reg"; "Liber Regum IV"; "4 Kgs." ]); + ("esdras_2", [ "2 Esd."; "2 Esdr"; "Liber Esdrae"; "2 Esdras" ]); + ("tobit", [ "Tob"; "Liber Tobiae"; "Tobias" ]); + ("judith", [ "Judith"; "Iudith"; "Liber Iudith"; "Jth" ]); + ("esther", [ "Esther"; "Esth"; "Liber Esther" ]); + ("proverbs", [ "Prov"; "Proverbs" ]); + ("song_of_songs", [ "Song"; "Cant."; "Canticle of Canticles" ]); + ("wisdom", [ "Wis"; "Wis."; "Sap"; "Liber Sapientiae"; "Wisdom" ]); + ("ecclesiasticus", [ "Ecclus"; "Sir"; "Eccli"; "Ecclesiasticus" ]); + ("isaiah", [ "Isa"; "Isa."; "Isai"; "Isaias Propheta"; "Isaias" ]); + ("jeremiah", [ "Jer"; "Ier"; "Ieremias Propheta"; "Jeremias" ]); + ("ezekiel", [ "Ezech"; "Ezek"; "Ezechiel Propheta"; "Ezechiel" ]); + ("daniel", [ "Dan"; "Daniel Propheta"; "Daniel" ]); + ("osee", [ "Osee"; "Osee Propheta" ]); + ("joel", [ "Joel"; "Ioel"; "Ioel Propheta" ]); + ("jonas", [ "Jonas"; "Ionae"; "Ionas Propheta" ]); + ("malachi", [ "Mal"; "Malach"; "Malachias Propheta"; "Malachias" ]); + ("matthew", [ "Matt"; "Matt."; "Matth"; "Evangelium secundum Matthaeum"; "Matthew" ]); + ("mark", [ "Mark"; "Marc"; "Evangelium secundum Marcum" ]); + ("luke", [ "Luke"; "Luc"; "Evangelium secundum Lucam" ]); + ("john", [ "John"; "Ioann"; "Evangelium secundum Ioannem" ]); + ("acts", [ "Acts"; "Act"; "Actus Apostolorum"; "Acts of the Apostles" ]); + ("romans", [ "Rom"; "Epistola ad Romanos"; "Romans" ]); + ("corinthians_1", [ "1 Cor"; "1 Cor."; "Epistola I ad Corinthios"; "1 Corinthians" ]); + ("corinthians_2", [ "2 Cor"; "2 Cor."; "Epistola II ad Corinthios"; "2 Corinthians" ]); + ("galatians", [ "Gal"; "Epistola ad Galatas"; "Galatians" ]); + ("ephesians", [ "Eph"; "Eph."; "Ephes"; "Epistola ad Ephesios"; "Ephesians" ]); + ("philippians", [ "Phil"; "Epistola ad Philippenses"; "Philippians" ]); + ("colossians", [ "Col"; "Col."; "Epistola ad Colossenses"; "Colossians" ]); + ("thessalonians_1", [ "1 Thess"; "1 Thess."; "Epistola I ad Thessalonicenses"; "1 Thessalonians" ]); + ("thessalonians_2", [ "2 Thess"; "Epistola II ad Thessalonicenses"; "2 Thessalonians" ]); + ("timothy_1", [ "1 Tim."; "1 Tim"; "Epistola I ad Timotheum"; "1 Timothy" ]); + ("timothy_2", [ "2 Tim"; "2 Tim."; "Epistola II ad Timotheum"; "2 Timothy" ]); + ("titus", [ "Titus"; "Tit"; "Epistola ad Titum" ]); + ("hebrews", [ "Heb"; "Hebr"; "Epistola ad Hebraeos"; "Hebrews" ]); + ("james", [ "Jas"; "James"; "Iac"; "Epistola beati Iacobi Apostoli" ]); + ("peter_1", [ "1 Pet"; "1 Pet."; "1 Petri"; "Epistola I beati Petri Apostoli"; "1 Peter" ]); + ("peter_2", [ "2 Pet."; "2 Petri"; "Epistola II beati Petri Apostoli"; "2 Pet"; "2 Peter" ]); + ("john_1", [ "1 John"; "1 Ioann"; "Epistola beati Ioannis Apostoli" ]); (* "Apoc" is the Vulgate spelling and "Rev" its modern equivalent, but BOTH sit inside Vulgate-tradition data, so both resolve to the same Vulgate id here -- see book.mli's note by [apocalypse] never being an [of_token] result under that name. Do not add "revelation" as a spelling: it exists only as a tradition target (below), and giving it an [of_token] entry would let one book carry two different ids. *) - ("apocalypse", [ "Apoc"; "Rev" ]) ] + ("apocalypse", [ "Apoc"; "Rev"; "Liber Apocalypsis"; "Apocalypse" ]) ] (* Targets a tradition can map ONTO that the Vulgate data never cites directly. Present so [tradition_of_fields] can validate both sides. @@ -70,16 +70,34 @@ let table = "Sir" and "Rev" already resolve to the Vulgate ids [ecclesiasticus] and [apocalypse] above, so a modern-numbering tradition maps ONTO these targets rather than data ever citing them directly. *) -let tradition_targets = - [ "kings_1"; "kings_2"; "nehemiah"; "sirach"; "hosea"; "jonah"; "revelation" ] + +(* The modern-numbering targets. They have table rows so that colitur's OWN + rendered output re-parses: with --sigla-tradition modern the book prints + as "1 Reg" or "1 Kings", and a user copying that back into an overlay must + get it read correctly. The shipped data never cites them directly, which + is why they are listed apart. *) +let tradition_target_table = + [ + ("kings_1", [ "1 Reg"; "Liber Regum I"; "1 Kgs"; "1 Kings" ]); + ("kings_2", [ "2 Reg"; "Liber Regum II"; "2 Kgs"; "2 Kings" ]); + ("nehemiah", [ "Neh"; "Liber Nehemiae"; "Nehemiah" ]); + ("sirach", [ "Liber Ecclesiastici"; "Sirach" ]); + ("hosea", [ "Os"; "Hos"; "Hosea" ]); + ("jonah", [ "Ion"; "Jon"; "Jonah" ]); + ("revelation", [ "Apocalypsis"; "Revelation" ]); + ] + +let tradition_targets = List.map fst tradition_target_table let all = List.map fst table @ tradition_targets let tokens = - List.concat_map (fun (id, sp) -> List.map (fun s -> (s, id)) sp) table + List.concat_map + (fun (id, sp) -> List.map (fun s -> (s, id)) sp) + (table @ tradition_target_table) let default_spelling id = - match List.assoc_opt id table with + match List.assoc_opt id (table @ tradition_target_table) with | Some (first :: _) -> first | Some [] | None -> id diff --git a/lib/citation/parse.ml b/lib/citation/parse.ml index 45fbb72..2f2316e 100644 --- a/lib/citation/parse.ml +++ b/lib/citation/parse.ml @@ -9,7 +9,41 @@ let split_on c s = String.split_on_char c s |> List.map String.trim (* The book is the longest leading run of non-digit words, allowing one leading ordinal ("1 Cor", "3 Kings"). Everything after it is the reference tail. *) +(* Longest REGISTERED token that prefixes [s] and is followed by a space and + a digit. This is what lets a MULTI-WORD title parse: the heuristic below + stops at the first space, so "Evangelium secundum Lucam 5:12-14" would + otherwise split as the book "Evangelium" and fail. + + Longest-match matters and is not decoration: "Liber Regum III" and + "Liber Regum IV" share a prefix with each other, and a shortest-match + would read both as some other book entirely. *) +let longest_token_prefix s = + let n = String.length s in + let best = ref None in + List.iter + (fun (tok, _) -> + let tl = String.length tok in + if + tl < n + && String.sub s 0 tl = tok + && s.[tl] = ' ' + (* a digit must follow, or "Job" would swallow the start of a + different book whose name merely begins the same way *) + && (let j = ref (tl + 1) in + while !j < n && s.[!j] = ' ' do incr j done; + !j < n && s.[!j] >= '0' && s.[!j] <= '9') + then + match !best with + | Some (b, _) when String.length b >= tl -> () + | _ -> best := Some (tok, String.trim (String.sub s tl (n - tl))) + ) + Book.tokens; + !best + let split_book s = + match longest_token_prefix s with + | Some (book, tail) when tail <> "" -> Some (book, tail) + | _ -> let n = String.length s in let i = ref 0 in (* optional leading ordinal digit *) @@ -25,7 +59,21 @@ let split_book s = let tail = String.trim (String.sub s !i (n - !i)) in if book = "" || tail = "" then None else Some (book, tail) -let int_opt s = int_of_string_opt (String.trim s) +(* A citation number is PLAIN DIGITS and positive -- nothing else. + [int_of_string_opt] also accepts OCaml's own integer-literal syntax, so + "1_1" would read as 11 and "+5" as 5: a transcription typo silently + becoming a DIFFERENT chapter, which nothing downstream could detect. A + user overlay supplies arbitrary strings, so this is reachable, not + theoretical. Chapter and verse numbering both start at 1, so zero is + rejected too. *) +let int_opt s = + let s = String.trim s in + let ok = + s <> "" + && String.for_all (function '0' .. '9' -> true | _ -> false) s + in + if not ok then None + else match int_of_string_opt s with Some n when n > 0 -> Some n | _ -> None (* "20-32" -> {first=20; last=Some 32}; "21" -> {first=21; last=None} *) let parse_range s = @@ -33,7 +81,9 @@ let parse_range s = | [ a ] -> ( match int_opt a with Some f -> Some { first = f; last = None } | None -> None) | [ a; b ] -> ( match (int_opt a, int_opt b) with - | Some f, Some l -> Some { first = f; last = Some l } + (* A descending range ("1:20-10") is always a transcription error; + accepting it would render back out as a citation nobody can follow. *) + | Some f, Some l when l >= f -> Some { first = f; last = Some l } | _ -> None) | _ -> None diff --git a/lib/kernel/layer.ml b/lib/kernel/layer.ml index ec074a7..f069546 100644 --- a/lib/kernel/layer.ml +++ b/lib/kernel/layer.ml @@ -85,11 +85,11 @@ let load rank_of_sexp path = unterminated list or string) rather than [Sexplib.Sexp.Parse_error], so a catch-all here -- placed last among the exception branches -- is what actually keeps every parse failure inside [Error] instead of escaping. *) - | exception exn -> Error (Printf.sprintf "%s: %s" path (Printexc.to_string exn)) + | exception exn -> Error (Printf.sprintf "%s: %s" path (Sexp_error.humanise (Printexc.to_string exn))) | sexp -> ( match t_of_sexp rank_of_sexp sexp with | t -> Ok { t with entries = canonical t.entries } (* [rank_of_sexp] is caller-supplied and may raise anything, not only [Of_sexp_error] -- mirrors [Overlay.load]'s catch-all, so "never as an exception" (layer.mli) actually holds. *) - | exception exn -> Error (Printf.sprintf "%s: %s" path (Printexc.to_string exn))) + | exception exn -> Error (Printf.sprintf "%s: %s" path (Sexp_error.humanise (Printexc.to_string exn)))) diff --git a/lib/kernel/overlay.ml b/lib/kernel/overlay.ml index 58d8847..516379d 100644 --- a/lib/kernel/overlay.ml +++ b/lib/kernel/overlay.ml @@ -132,23 +132,6 @@ let fill_defaults ~id sexp = actually reach a user into the vocabulary of the file they are looking at. Anything unrecognised passes through verbatim rather than being reworded into something possibly wrong. *) -let humanise_error msg = - let replace ~sub ~by s = - let n = String.length sub and len = String.length s in - let rec go i acc = - if i > len - n then acc ^ String.sub s i (len - i) - else if String.equal (String.sub s i n) sub then go (i + n) (acc ^ by) - else go (i + 1) (acc ^ String.make 1 s.[i]) - in - if n = 0 then s else go 0 "" - in - msg - |> replace ~sub:"lib/kernel/celebration.ml.t_of_sexp" ~by:"celebration" - |> replace ~sub:"lib/kernel/colour.ml.t_of_sexp" ~by:"colour" - |> replace ~sub:"lib/kernel/subject.ml.t_of_sexp" ~by:"subject" - |> replace ~sub:"lib/kernel/date_spec.ml.t_of_sexp" ~by:"date" - |> replace ~sub:"lib/kernel/overlay.ml.directive_of_sexp" ~by:"directive" - let load rank_of_sexp path = match Sexplib.Sexp.load_sexp path with | exception Sys_error msg -> Error msg @@ -157,7 +140,8 @@ let load rank_of_sexp path = [Sexplib.Sexp.Parse_error], so a catch-all here -- placed last among the exception branches -- is what actually keeps every parse failure inside [Error] instead of escaping. *) - | exception exn -> Error (Printf.sprintf "%s: %s" path (Printexc.to_string exn)) + | exception exn -> + Error (Printf.sprintf "%s: %s" path (Sexp_error.humanise (Printexc.to_string exn))) | sexp -> ( (* The overlay's own [id] is needed to default [layer], so read it off the raw sexp first. If it is missing or malformed the derived parser @@ -174,4 +158,4 @@ let load rank_of_sexp path = match t_of_sexp rank_of_sexp (fill_defaults ~id sexp) with | t -> Ok t | exception exn -> - Error (Printf.sprintf "%s: %s" path (humanise_error (Printexc.to_string exn)))) + Error (Printf.sprintf "%s: %s" path (Sexp_error.humanise (Printexc.to_string exn)))) diff --git a/lib/kernel/overlay_ini.ml b/lib/kernel/overlay_ini.ml index 6b6249f..09f6d52 100644 --- a/lib/kernel/overlay_ini.ml +++ b/lib/kernel/overlay_ini.ml @@ -37,7 +37,18 @@ let parse_sections text = end else match String.index_opt line '=' with - | None -> err "line %d: %S is neither a [section] nor a key = value line" n line + | None -> + (* Echo at most a little of the line. Pointing at line N is + what locates the problem; reproducing the whole line adds + nothing and, when someone has pointed a --lang or --overlay + flag at a file that is not a calendar at all, quietly + copies that file's contents into stderr and any log + collecting it. *) + let shown = + if String.length line > 40 then String.sub line 0 37 ^ "..." + else line + in + err "line %d: %S is neither a [section] nor a key = value line" n shown | Some i -> if !cur = None then err "line %d: %S appears before any [section] header" n line diff --git a/lib/kernel/sexp_error.ml b/lib/kernel/sexp_error.ml new file mode 100644 index 0000000..88cc139 --- /dev/null +++ b/lib/kernel/sexp_error.ml @@ -0,0 +1,177 @@ +(* SPDX-License-Identifier: AGPL-3.0-or-later *) + +(* Turn a raw sexplib exception string into something a person editing an + overlay can act on. + + The derived parsers report failures as [Of_sexp_error] carrying the + OCaml source path of the converter that failed, e.g. + + (Of_sexp_error "lib/rites/rite_ef/vocab_ef.ml.rank_of_sexp: + unexpected variant constructor" (invalid_sexp Class9)) + + which names a file the reader does not have and buries the one useful + token (Class9) at the end. A user writing a diocesan calendar is the + most likely person to hit this and the least likely to read OCaml. + + An earlier version of this lived in overlay.ml and rewrote five + hardcoded module paths; anything else -- a rank, a layer entry, the + top-level record -- came through raw. This one is generic, so a + converter added later is covered without being listed. *) + +let ends_with ~suffix s = + let ls = String.length s and lf = String.length suffix in + ls >= lf && String.sub s (ls - lf) lf = suffix + +(* "lib/kernel/layer.ml.entry_of_sexp" -> "entry" + "lib/kernel/overlay.ml.t_of_sexp" -> "overlay" (t is the module itself) *) +let noun_of_converter tok = + match String.index_opt tok '/' with + | None when not (String.length tok > 4 && String.sub tok 0 4 = "lib/") -> None + | _ -> + let dot_ml = ".ml." in + let n = String.length tok and d = String.length dot_ml in + let rec find i = + if i > n - d then None + else if String.sub tok i d = dot_ml then Some i + else find (i + 1) + in + Option.bind (find 0) (fun i -> + let fn = String.sub tok (i + d) (n - i - d) in + if not (ends_with ~suffix:"_of_sexp" fn) then None + else + let base = String.sub fn 0 (String.length fn - 8) in + if base <> "t" then Some base + else + (* fall back to the module's own name *) + let path = String.sub tok 0 i in + let start = + match String.rindex_opt path '/' with + | Some j -> j + 1 + | None -> 0 + in + Some (String.sub path start (String.length path - start))) + +let replace ~sub ~by s = + let n = String.length sub and len = String.length s in + if n = 0 then s + else + let b = Buffer.create len in + let i = ref 0 in + while !i <= len - n do + if String.sub s !i n = sub then begin + Buffer.add_string b by; + i := !i + n + end + else begin + Buffer.add_char b s.[!i]; + incr i + end + done; + Buffer.add_string b (String.sub s !i (len - !i)); + Buffer.contents b + +(* Every whitespace/paren-delimited token that looks like a converter path. *) +let rec humanise msg = + let is_sep c = c = ' ' || c = '"' || c = '(' || c = ')' || c = '\n' in + let out = ref msg in + let n = String.length msg in + let i = ref 0 in + while !i < n do + if is_sep msg.[!i] then incr i + else begin + let start = !i in + while !i < n && not (is_sep msg.[!i]) do incr i done; + let tok = String.sub msg start (!i - start) in + let tok = if ends_with ~suffix:":" tok then String.sub tok 0 (String.length tok - 1) else tok in + match noun_of_converter tok with + | Some noun -> out := replace ~sub:tok ~by:noun !out + | None -> () + end + done; + !out + (* sexplib's own phrasing, in the reader's terms. Order matters: the + longer "... for record expected" forms are rewritten before the + shorter ones so no stray "expected" is left behind. *) + |> replace ~sub:"unexpected variant constructor" ~by:"is not one of the allowed values" + |> replace ~sub:"list instead of atom for record expected" + ~by:"expected a record, found a plain value" + |> replace ~sub:"atom instead of list for record expected" + ~by:"expected a record, found a plain value" + |> replace ~sub:"extra fields" ~by:"unknown field(s)" + |> replace ~sub:"element of list" ~by:"item" + |> strip_wrapper + +(* [(Of_sexp_error "MSG" (invalid_sexp VALUE))] -> [MSG (at VALUE)]. + The wrapper is the parser's own structure, not anything the reader + wrote, and leaving it in makes an error look like more sexp to debug. A + long VALUE is truncated: the offending FIELD is what identifies the + problem, and echoing an entire record -- or, when the file is not a + calendar at all, a line of its contents -- is noise at best and leaks + file content into logs at worst. *) +and strip_wrapper msg = + (* sexplib PRETTY-PRINTS the exception, so the wrapper is followed by a + newline and indentation rather than a single space. Collapse all + whitespace first, or the prefix match silently never fires and every + message comes through raw -- which is exactly what happened on the + first attempt at this. *) + let msg = + String.concat " " + (List.filter (fun w -> w <> "") + (String.split_on_char ' ' + (String.map (function '\n' | '\t' | '\r' -> ' ' | c -> c) msg))) + in + let msg = String.trim msg in + let strip_prefix p s = + let lp = String.length p in + if String.length s >= lp && String.sub s 0 lp = p then + Some (String.sub s lp (String.length s - lp)) + else None + in + match strip_prefix "(Of_sexp_error " msg with + | None -> msg + | Some rest -> + let rest = String.trim rest in + let body, value = + match String.index_opt rest '"' with + | Some 0 -> ( + match String.index_from_opt rest 1 '"' with + | Some close -> + let m = String.sub rest 1 (close - 1) in + let tail = String.trim (String.sub rest (close + 1) + (String.length rest - close - 1)) in + (m, tail) + | None -> (rest, "")) + | _ -> (rest, "") + in + let value = + match strip_prefix "(invalid_sexp " value with + | Some v -> + let v = String.trim v in + (* Drop the closing parens of BOTH wrappers -- invalid_sexp's and + Of_sexp_error's -- keeping any that belong to the value + itself, by removing only the excess over what the value + opens. *) + let v = + let opens = ref 0 and closes = ref 0 in + String.iter + (function '(' -> incr opens | ')' -> incr closes | _ -> ()) + v; + let excess = ref (!closes - !opens) in + let b = Buffer.create (String.length v) in + let n = String.length v in + let i = ref (n - 1) in + let tail = ref [] in + while !i >= 0 do + (if v.[!i] = ')' && !excess > 0 then decr excess + else tail := v.[!i] :: !tail); + decr i + done; + List.iter (Buffer.add_char b) !tail; + Buffer.contents b + in + let v = String.concat " " (String.split_on_char '\n' v) in + let v = String.trim v in + if String.length v > 60 then String.sub v 0 57 ^ "..." else v + | None -> "" + in + if value = "" then body else body ^ " (at " ^ value ^ ")" diff --git a/lib/kernel/sexp_error.mli b/lib/kernel/sexp_error.mli new file mode 100644 index 0000000..d3de75b --- /dev/null +++ b/lib/kernel/sexp_error.mli @@ -0,0 +1,4 @@ +(* SPDX-License-Identifier: AGPL-3.0-or-later *) + +(** Human-readable form of a raw sexplib exception string. *) +val humanise : string -> string |