(* Title: Pure/Thy/thy_syntax.ML
Author: Makarius
Superficial theory syntax: tokens and spans.
*)
signature THY_SYNTAX =
sig
val parse_tokens: Scan.lexicon * Scan.lexicon -> Position.T -> string -> Token.T list
val reports_of_tokens: Token.T list -> bool * (Position.report * string) list
val present_token: Token.T -> Output.output
datatype span_kind = Command of string * Position.T | Ignored | Malformed
datatype span = Span of span_kind * Token.T list
val span_kind: span -> span_kind
val span_content: span -> Token.T list
val present_span: span -> Output.output
val parse_spans: Token.T list -> span list
type element = {head: span, proof: span list, proper_proof: bool}
val parse_elements: span list -> element list
end;
structure Thy_Syntax: THY_SYNTAX =
struct
(** tokens **)
(* parse *)
fun parse_tokens lexs pos =
Source.of_string #>
Symbol.source #>
Token.source {do_recover = SOME false} (K lexs) pos #>
Source.exhaust;
(* present *)
local
val token_kind_markup =
fn Token.Command => (Markup.command, "")
| Token.Keyword => (Markup.keyword, "")
| Token.Ident => (Markup.empty, "")
| Token.LongIdent => (Markup.empty, "")
| Token.SymIdent => (Markup.empty, "")
| Token.Var => (Markup.var, "")
| Token.TypeIdent => (Markup.tfree, "")
| Token.TypeVar => (Markup.tvar, "")
| Token.Nat => (Markup.empty, "")
| Token.Float => (Markup.empty, "")
| Token.String => (Markup.string, "")
| Token.AltString => (Markup.altstring, "")
| Token.Verbatim => (Markup.verbatim, "")
| Token.Space => (Markup.empty, "")
| Token.Comment => (Markup.comment, "")
| Token.InternalValue => (Markup.empty, "")
| Token.Error msg => (Markup.bad, msg)
| Token.Sync => (Markup.control, "")
| Token.EOF => (Markup.control, "");
fun token_markup tok =
if Token.keyword_with (not o Symbol.is_ascii_identifier) tok
then (Markup.operator, "")
else
let
val kind = Token.kind_of tok;
val props =
if kind = Token.Command
then Markup.properties [(Markup.nameN, Token.content_of tok)]
else I;
val (markup, txt) = token_kind_markup kind;
in (props markup, txt) end;
fun reports_of_token tok =
let
val malformed_symbols =
Symbol_Pos.explode (Token.source_position_of tok)
|> map_filter (fn (sym, pos) =>
if Symbol.is_malformed sym
then SOME ((pos, Markup.bad), "Malformed symbolic character") else NONE);
val is_malformed = Token.is_error tok orelse not (null malformed_symbols);
val (markup, txt) = token_markup tok;
val reports = ((Token.position_of tok, markup), txt) :: malformed_symbols;
in (is_malformed, reports) end;
in
fun reports_of_tokens toks =
let val results = map reports_of_token toks
in (exists fst results, maps snd results) end;
fun present_token tok =
Markup.enclose (fst (token_markup tok)) (Output.output (Token.unparse tok));
end;
(** spans **)
(* type span *)
datatype span_kind = Command of string * Position.T | Ignored | Malformed;
datatype span = Span of span_kind * Token.T list;
fun span_kind (Span (k, _)) = k;
fun span_content (Span (_, toks)) = toks;
val present_span = implode o map present_token o span_content;
(* parse *)
local
fun make_span toks =
if not (null toks) andalso Token.is_command (hd toks) then
Span (Command (Token.content_of (hd toks), Token.position_of (hd toks)), toks)
else if forall (not o Token.is_proper) toks then Span (Ignored, toks)
else Span (Malformed, toks);
fun flush (result, span) = if null span then (result, span) else (rev span :: result, []);
in
fun parse_spans toks =
fold (fn tok => Token.is_command tok ? flush #> apsnd (cons tok)) toks ([], [])
|> flush
|> #1 |> rev |> map make_span;
end;
(** specification elements: commands with optional proof **)
type element = {head: span, proof: span list, proper_proof: bool};
fun make_element head proof proper_proof =
{head = head, proof = proof, proper_proof = proper_proof};
(* scanning spans *)
val eof = Span (Command ("", Position.none), []);
fun is_eof (Span (Command ("", _), _)) = true
| is_eof _ = false;
val not_eof = not o is_eof;
val stopper = Scan.stopper (K eof) is_eof;
(* parse *)
local
fun command_with pred =
Scan.one (fn (Span (Command (name, _), _)) => pred name | _ => false);
val proof = Scan.pass 1 (Scan.repeat (Scan.depend (fn d =>
if d <= 0 then Scan.fail
else
command_with Keyword.is_qed_global >> pair ~1 ||
command_with Keyword.is_proof_goal >> pair (d + 1) ||
(if d = 0 then Scan.fail else command_with Keyword.is_qed >> pair (d - 1)) ||
Scan.unless (command_with Keyword.is_theory) (Scan.one not_eof) >> pair d)) -- Scan.state);
val element =
command_with Keyword.is_theory_goal -- proof
>> (fn (a, (bs, d)) => make_element a bs (d >= 0)) ||
Scan.one not_eof >> (fn a => make_element a [] true);
in
val parse_elements =
Source.of_list #>
Source.source stopper (Scan.bulk element) NONE #>
Source.exhaust;
end;
end;