diff options
Diffstat (limited to 'lib/unicode.ml')
| -rw-r--r-- | lib/unicode.ml | 140 |
1 files changed, 105 insertions, 35 deletions
diff --git a/lib/unicode.ml b/lib/unicode.ml index 959ccaf73c..f193c4e0f8 100644 --- a/lib/unicode.ml +++ b/lib/unicode.ml @@ -8,13 +8,14 @@ (** Unicode utilities *) -type status = Letter | IdentPart | Symbol | Unknown +type status = Letter | IdentPart | Symbol | IdentSep | Unknown (* The following table stores classes of Unicode characters that - are used by the lexer. There are 3 different classes so 2 bits are - allocated for each character. We only use 16 bits over the 31 bits - to simplify the masking process. (This choice seems to be a good - trade-off between speed and space after some benchmarks.) *) + are used by the lexer. There are 5 different classes so 3 bits + are allocated for each character. We encode the masks of 8 + characters per word, thus using 24 bits over the 31 available + bits. (This choice seems to be a good trade-off between speed + and space after some benchmarks.) *) (* A 256 KiB table, initially filled with zeros. *) let table = Array.make (1 lsl 17) 0 @@ -24,14 +25,15 @@ let table = Array.make (1 lsl 17) 0 define the position of the pattern in the word. Notice that pattern "00" means "undefined". *) let mask i = function - | Letter -> 1 lsl ((i land 7) lsl 1) (* 01 *) - | IdentPart -> 2 lsl ((i land 7) lsl 1) (* 10 *) - | Symbol -> 3 lsl ((i land 7) lsl 1) (* 11 *) - | Unknown -> 0 lsl ((i land 7) lsl 1) (* 00 *) + | Letter -> 1 lsl ((i land 7) * 3) (* 001 *) + | IdentPart -> 2 lsl ((i land 7) * 3) (* 010 *) + | Symbol -> 3 lsl ((i land 7) * 3) (* 011 *) + | IdentSep -> 4 lsl ((i land 7) * 3) (* 100 *) + | Unknown -> 0 lsl ((i land 7) * 3) (* 000 *) -(* Helper to reset 2 bits in a word. *) +(* Helper to reset 3 bits in a word. *) let reset_mask i = - lnot (3 lsl ((i land 7) lsl 1)) + lnot (7 lsl ((i land 7) * 3)) (* Initialize the lookup table from a list of segments, assigning a status to every character of each segment. The order of these @@ -50,13 +52,14 @@ let mk_lookup_table_from_unicode_tables_for status tables = (* Look up into the table and interpret the found pattern. *) let lookup x = - let v = (table.(x lsr 3) lsr ((x land 7) lsl 1)) land 3 in + let v = (table.(x lsr 3) lsr ((x land 7) * 3)) land 7 in if v = 1 then Letter else if v = 2 then IdentPart else if v = 3 then Symbol + else if v = 4 then IdentSep else Unknown -(* [classify] discriminates between 3 different kinds of +(* [classify] discriminates between 5 different kinds of symbols based on the standard unicode classification (extracted from Camomile). *) let classify = @@ -67,13 +70,13 @@ let classify = Unicodetable.sm; (* Symbol, maths. *) Unicodetable.sc; (* Symbol, currency. *) Unicodetable.so; (* Symbol, modifier. *) - Unicodetable.pd; (* Punctation, dash. *) - Unicodetable.pc; (* Punctation, connector. *) - Unicodetable.pe; (* Punctation, open. *) - Unicodetable.ps; (* Punctation, close. *) - Unicodetable.pi; (* Punctation, initial quote. *) - Unicodetable.pf; (* Punctation, final quote. *) - Unicodetable.po; (* Punctation, other. *) + Unicodetable.pd; (* Punctuation, dash. *) + Unicodetable.pc; (* Punctuation, connector. *) + Unicodetable.pe; (* Punctuation, open. *) + Unicodetable.ps; (* Punctution, close. *) + Unicodetable.pi; (* Punctuation, initial quote. *) + Unicodetable.pf; (* Punctuation, final quote. *) + Unicodetable.po; (* Punctuation, other. *) ]; mk_lookup_table_from_unicode_tables_for Letter [ @@ -107,14 +110,14 @@ let classify = [(0x02074, 0x02079)]; (* Superscript 4-9. *) single 0x0002E; (* Dot. *) ]; - mk_lookup_table_from_unicode_tables_for Letter + mk_lookup_table_from_unicode_tables_for IdentSep [ single 0x005F; (* Underscore. *) single 0x00A0; (* Non breaking space. *) ]; mk_lookup_table_from_unicode_tables_for IdentPart [ - single 0x0027; (* Special space. *) + single 0x0027; (* Single quote. *) ]; (* Lookup *) lookup @@ -163,24 +166,75 @@ let is_utf8 s = in try check 0 with End_of_input -> true | Invalid_argument _ -> false +(* Escape string if it contains non-utf8 characters *) + +let escaped_non_utf8 s = + let mk_escape x = Printf.sprintf "%%%X" x in + let buff = Buffer.create (String.length s * 3) in + let rec process_trailing_aux i j = + if i = j then i else + match String.unsafe_get s i with + | '\128'..'\191' -> process_trailing_aux (i+1) j + | _ -> i in + let process_trailing i n = + let j = if i+n-1 >= String.length s then i+1 else process_trailing_aux (i+1) (i+n) in + (if j = i+n then + Buffer.add_string buff (String.sub s i n) + else + let v = Array.init (j-i) (fun k -> mk_escape (Char.code s.[i+k])) in + Buffer.add_string buff (String.concat "" (Array.to_list v))); + j in + let rec process i = + if i >= String.length s then Buffer.contents buff else + let c = String.unsafe_get s i in + match c with + | '\000'..'\127' -> Buffer.add_char buff c; process (i+1) + | '\128'..'\191' | '\248'..'\255' -> Buffer.add_string buff (mk_escape (Char.code c)); process (i+1) + | '\192'..'\223' -> process (process_trailing i 2) + | '\224'..'\239' -> process (process_trailing i 3) + | '\240'..'\247' -> process (process_trailing i 4) + in + process 0 + +let escaped_if_non_utf8 s = + if is_utf8 s then s else escaped_non_utf8 s + (* Check the well-formedness of an identifier *) +let is_valid_ident_initial = function + | Letter | IdentSep -> true + | IdentPart | Symbol | Unknown -> false + let initial_refutation j n s = - match classify n with - | Letter -> None - | _ -> + if is_valid_ident_initial (classify n) then None + else let c = String.sub s 0 j in Some (false, "Invalid character '"^c^"' at beginning of identifier \""^s^"\".") +let is_valid_ident_trailing = function + | Letter | IdentSep | IdentPart -> true + | Symbol | Unknown -> false + let trailing_refutation i j n s = - match classify n with - | Letter | IdentPart -> None - | _ -> + if is_valid_ident_trailing (classify n) then None + else let c = String.sub s i j in Some (false, "Invalid character '"^c^"' in identifier \""^s^"\".") +let is_unknown = function + | Unknown -> true + | Letter | IdentSep | IdentPart | Symbol -> false + +let is_ident_part = function + | IdentPart -> true + | Letter | IdentSep | Symbol | Unknown -> false + +let is_ident_sep = function + | IdentSep -> true + | Letter | IdentPart | Symbol | Unknown -> false + let ident_refutation s = if s = ".." then None else try let j, n = next_utf8 s 0 in @@ -198,7 +252,7 @@ let ident_refutation s = |x -> x with | End_of_input -> Some (true,"The empty string is not an identifier.") - | Invalid_argument _ -> Some (true,s^": invalid utf8 sequence.") + | Invalid_argument _ -> Some (true,escaped_non_utf8 s^": invalid utf8 sequence.") let lowercase_unicode = let tree = Segmenttree.make Unicodetable.to_lower in @@ -214,6 +268,26 @@ let lowercase_first_char s = let j, n = next_utf8 s 0 in utf8_of_unicode (lowercase_unicode n) +let split_at_first_letter s = + let n, v = next_utf8 s 0 in + if ((* optim *) n = 1 && s.[0] != '_') || not (is_ident_sep (classify v)) then None + else begin + let n = ref n in + let p = ref 0 in + while !n < String.length s && + let n', v = next_utf8 s !n in + p := n'; + (* Test if not letter *) + ((* optim *) n' = 1 && (s.[!n] = '_' || s.[!n] = '\'')) + || let st = classify v in + is_ident_sep st || is_ident_part st + do n := !n + !p + done; + let s1 = String.sub s 0 !n in + let s2 = String.sub s !n (String.length s - !n) in + Some (s1,s2) + end + (** For extraction, we need to encode unicode character into ascii ones *) let is_basic_ascii s = @@ -268,9 +342,7 @@ let utf8_length s = | '\192'..'\223' -> nc := 1 (* expect 1 continuation byte *) | '\224'..'\239' -> nc := 2 (* expect 2 continuation bytes *) | '\240'..'\247' -> nc := 3 (* expect 3 continuation bytes *) - | '\248'..'\251' -> nc := 4 (* expect 4 continuation bytes *) - | '\252'..'\253' -> nc := 5 (* expect 5 continuation bytes *) - | '\254'..'\255' -> nc := 0 (* invalid byte *) + | '\248'..'\255' -> nc := 0 (* invalid byte *) end ; incr p ; while !p < len && !nc > 0 do @@ -299,9 +371,7 @@ let utf8_sub s start_u len_u = | '\192'..'\223' -> nc := 1 (* expect 1 continuation byte *) | '\224'..'\239' -> nc := 2 (* expect 2 continuation bytes *) | '\240'..'\247' -> nc := 3 (* expect 3 continuation bytes *) - | '\248'..'\251' -> nc := 4 (* expect 4 continuation bytes *) - | '\252'..'\253' -> nc := 5 (* expect 5 continuation bytes *) - | '\254'..'\255' -> nc := 0 (* invalid byte *) + | '\248'..'\255' -> nc := 0 (* invalid byte *) end ; incr p ; while !p < len_b && !nc > 0 do |