%% %% %CopyrightBegin% %% %% Copyright Ericsson AB 1996-2013. All Rights Reserved. %% %% The contents of this file are subject to the Erlang Public License, %% Version 1.1, (the "License"); you may not use this file except in %% compliance with the License. You should have received a copy of the %% Erlang Public License along with this software. If not, it can be %% retrieved online at http://www.erlang.org/. %% %% Software distributed under the License is distributed on an "AS IS" %% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See %% the License for the specific language governing rights and limitations %% under the License. %% %% %CopyrightEnd% %% -module(io_lib_pretty). %%% Pretty printing Erlang terms %%% %%% In this module "print" means the formatted printing while "write" %%% means just writing out onto one line. -export([print/1,print/2,print/3,print/4,print/5,print/6]). %%% %%% Exported functions %%% %% print(Term) -> [Chars] %% print(Term, Column, LineLength, Depth) -> [Chars] %% Depth = -1 gives unlimited print depth. Use io_lib:write for atomic terms. -spec print(term()) -> io_lib:chars(). print(Term) -> print(Term, 1, 80, -1). %% print(Term, RecDefFun) -> [Chars] %% print(Term, Depth, RecDefFun) -> [Chars] %% RecDefFun = fun(Tag, NoFields) -> [FieldTag] | no %% Used by the shell for printing records and for Unicode. -type rec_print_fun() :: fun((Tag :: atom(), NFields :: non_neg_integer()) -> no | [FieldName :: atom()]). -type column() :: integer(). -type line_length() :: pos_integer(). -type depth() :: integer(). -type max_chars() :: integer(). -type chars() :: io_lib:chars(). -type option() :: {column, column()} | {line_length, line_length()} | {depth, depth()} | {max_chars, max_chars()} | {record_print_fun, rec_print_fun()} | {strings, boolean()} | {encoding, latin1 | utf8 | unicode}. -type options() :: [option()]. -spec print(term(), rec_print_fun()) -> chars(); (term(), options()) -> chars(). print(Term, Options) when is_list(Options) -> Col = proplists:get_value(column, Options, 1), Ll = proplists:get_value(line_length, Options, 80), D = proplists:get_value(depth, Options, -1), M = proplists:get_value(max_chars, Options, -1), RecDefFun = proplists:get_value(record_print_fun, Options, no_fun), Encoding = proplists:get_value(encoding, Options, epp:default_encoding()), Strings = proplists:get_value(strings, Options, true), print(Term, Col, Ll, D, M, RecDefFun, Encoding, Strings); print(Term, RecDefFun) -> print(Term, -1, RecDefFun). -spec print(term(), depth(), rec_print_fun()) -> chars(). print(Term, Depth, RecDefFun) -> print(Term, 1, 80, Depth, RecDefFun). -spec print(term(), column(), line_length(), depth()) -> chars(). print(Term, Col, Ll, D) -> print(Term, Col, Ll, D, _M=-1, no_fun, latin1, true). -spec print(term(), column(), line_length(), depth(), rec_print_fun()) -> chars(). print(Term, Col, Ll, D, RecDefFun) -> print(Term, Col, Ll, D, _M=-1, RecDefFun). -spec print(term(), column(), line_length(), depth(), max_chars(), rec_print_fun()) -> chars(). print(Term, Col, Ll, D, M, RecDefFun) -> print(Term, Col, Ll, D, M, RecDefFun, latin1, true). print(_, _, _, 0, _M, _RF, _Enc, _Str) -> "..."; print(Term, Col, Ll, D, M, RecDefFun, Enc, Str) when Col =< 0 -> print(Term, 1, Ll, D, M, RecDefFun, Enc, Str); print(Term, Col, Ll, D, M0, RecDefFun, Enc, Str) when is_tuple(Term); is_list(Term); is_bitstring(Term) -> If = {_S, Len} = print_length(Term, D, RecDefFun, Enc, Str), M = max_cs(M0, Len), if Len < Ll - Col, Len =< M -> write(If); true -> TInd = while_fail([-1, 4], fun(I) -> cind(If, Col, Ll, M, I, 0, 0) end, 1), pp(If, Col, Ll, M, TInd, indent(Col), 0, 0) end; print(Term, _Col, _Ll, _D, _M, _RF, _Enc, _Str) -> io_lib:write(Term). %%% %%% Local functions %%% max_cs(M, Len) when M < 0 -> Len; max_cs(M, _Len) -> M. -define(ATM(T), is_list(element(1, T))). -define(ATM_FLD(Field), ?ATM(element(4, element(1, Field)))). pp({_S, Len} = If, Col, Ll, M, _TInd, _Ind, LD, W) when Len < Ll - Col - LD, Len + W + LD =< M -> write(If); pp({{list,L}, _Len}, Col, Ll, M, TInd, Ind, LD, W) -> [$[, pp_list(L, Col + 1, Ll, M, TInd, indent(1, Ind), LD, $|, W + 1), $]]; pp({{tuple,true,L}, _Len}, Col, Ll, M, TInd, Ind, LD, W) -> [${, pp_tag_tuple(L, Col, Ll, M, TInd, Ind, LD, W + 1), $}]; pp({{tuple,false,L}, _Len}, Col, Ll, M, TInd, Ind, LD, W) -> [${, pp_list(L, Col + 1, Ll, M, TInd, indent(1, Ind), LD, $,, W + 1), $}]; pp({{record,[{Name,NLen} | L]}, _Len}, Col, Ll, M, TInd, Ind, LD, W) -> [Name, ${, pp_record(L, NLen, Col, Ll, M, TInd, Ind, LD, W + NLen+1), $}]; pp({{bin,S}, _Len}, Col, Ll, M, _TInd, Ind, LD, W) -> pp_binary(S, Col + 2, Ll, M, indent(2, Ind), LD, W); pp({S, _Len}, _Col, _Ll, _M, _TInd, _Ind, _LD, _W) -> S. %% Print a tagged tuple by indenting the rest of the elements %% differently to the tag. Tuple has size >= 2. pp_tag_tuple([{Tag,Tlen} | L], Col, Ll, M, TInd, Ind, LD, W) -> TagInd = Tlen + 2, Tcol = Col + TagInd, S = $,, if TInd > 0, TagInd > TInd -> Col1 = Col + TInd, Indent = indent(TInd, Ind), [Tag|pp_tail(L, Col1, Tcol, Ll, M, TInd, Indent, LD, S, W+Tlen)]; true -> Indent = indent(TagInd, Ind), [Tag, S | pp_list(L, Tcol, Ll, M, TInd, Indent, LD, S, W+Tlen+1)] end. pp_record([], _Nlen, _Col, _Ll, _M, _TInd, _Ind, _LD, _W) -> ""; pp_record({dots, _}, _Nlen, _Col, _Ll, _M, _TInd, _Ind, _LD, _W) -> "..."; pp_record([F | Fs], Nlen, Col0, Ll, M, TInd, Ind0, LD, W0) -> Nind = Nlen + 1, {Col, Ind, S, W} = rec_indent(Nind, TInd, Col0, Ind0, W0), {FS, FW} = pp_field(F, Col, Ll, M, TInd, Ind, last_depth(Fs, LD), W), [S, FS | pp_fields_tail(Fs, Col, Col + FW, Ll, M, TInd, Ind, LD, W + FW)]. pp_fields_tail([], _Col0, _Col, _Ll, _M, _TInd, _Ind, _LD, _W) -> ""; pp_fields_tail({dots, _}, _Col0, _Col, _M, _Ll, _TInd, _Ind, _LD, _W) -> ",..."; pp_fields_tail([{_, Len}=F | Fs], Col0, Col, Ll, M, TInd, Ind, LD, W) -> LD1 = last_depth(Fs, LD), ELen = 1 + Len, if LD1 =:= 0, ELen + 1 < Ll - Col, W + ELen + 1 =< M, ?ATM_FLD(F); LD1 > 0, ELen < Ll - Col - LD1, W + ELen + LD1 =< M, ?ATM_FLD(F) -> [$,, write_field(F) | pp_fields_tail(Fs, Col0, Col+ELen, Ll, M, TInd, Ind, LD, W+ELen)]; true -> {FS, FW} = pp_field(F, Col0, Ll, M, TInd, Ind, LD1, 0), [$,, $\n, Ind, FS | pp_fields_tail(Fs, Col0, Col0 + FW, Ll, M, TInd, Ind, LD, FW)] end. pp_field({_, Len}=Fl, Col, Ll, M, _TInd, _Ind, LD, W) when Len < Ll - Col - LD, Len + W + LD =< M -> {write_field(Fl), if ?ATM_FLD(Fl) -> Len; true -> Ll % force nl end}; pp_field({{field, Name, NameL, F}, _Len}, Col0, Ll, M, TInd, Ind0, LD, W0) -> {Col, Ind, S, W} = rec_indent(NameL, TInd, Col0, Ind0, W0 + NameL), {[Name, " = ", S | pp(F, Col, Ll, M, TInd, Ind, LD, W)], Ll}. % force nl rec_indent(RInd, TInd, Col0, Ind0, W0) -> Nl = (TInd > 0) and (RInd > TInd), DCol = case Nl of true -> TInd; false -> RInd end, Col = Col0 + DCol, Ind = indent(DCol, Ind0), S = case Nl of true -> [$\n | Ind]; false -> "" end, W = case Nl of true -> 0; false -> W0 end, {Col, Ind, S, W}. pp_list({dots, _}, _Col0, _Ll, _M, _TInd, _Ind, _LD, _S, _W) -> "..."; pp_list([E | Es], Col0, Ll, M, TInd, Ind, LD, S, W) -> {ES, WE} = pp_element(E, Col0, Ll, M, TInd, Ind, last_depth(Es, LD), W), [ES | pp_tail(Es, Col0, Col0 + WE, Ll, M, TInd, Ind, LD, S, W + WE)]. pp_tail([], _Col0, _Col, _Ll, _M, _TInd, _Ind, _LD, _S, _W) -> ""; pp_tail([{_, Len}=E | Es], Col0, Col, Ll, M, TInd, Ind, LD, S, W) -> LD1 = last_depth(Es, LD), ELen = 1 + Len, if LD1 =:= 0, ELen + 1 < Ll - Col, W + ELen + 1 =< M, ?ATM(E); LD1 > 0, ELen < Ll - Col - LD1, W + ELen + LD1 =< M, ?ATM(E) -> [$,, write(E) | pp_tail(Es, Col0, Col + ELen, Ll, M, TInd, Ind, LD, S, W+ELen)]; true -> {ES, WE} = pp_element(E, Col0, Ll, M, TInd, Ind, LD1, 0), [$,, $\n, Ind, ES | pp_tail(Es, Col0, Col0 + WE, Ll, M, TInd, Ind, LD, S, WE)] end; pp_tail({dots, _}, _Col0, _Col, _Ll, _M, _TInd, _Ind, _LD, S, _W) -> [S | "..."]; pp_tail({_, Len}=E, _Col0, Col, Ll, M, _TInd, _Ind, LD, S, W) when Len + 1 < Ll - Col - (LD + 1), Len + 1 + W + (LD + 1) =< M, ?ATM(E) -> [S | write(E)]; pp_tail(E, Col0, _Col, Ll, M, TInd, Ind, LD, S, _W) -> [S, $\n, Ind | pp(E, Col0, Ll, M, TInd, Ind, LD + 1, 0)]. pp_element({_, Len}=E, Col, Ll, M, _TInd, _Ind, LD, W) when Len < Ll - Col - LD, Len + W + LD =< M, ?ATM(E) -> {write(E), Len}; pp_element(E, Col, Ll, M, TInd, Ind, LD, W) -> {pp(E, Col, Ll, M, TInd, Ind, LD, W), Ll}. % force nl %% Reuse the list created by io_lib:write_binary()... pp_binary([LT,LT,S,GT,GT], Col, Ll, M, Ind, LD, W) -> N = erlang:max(8, erlang:min(Ll - Col, M - 4 - W) - LD), [LT,LT,pp_binary(S, N, N, Ind),GT,GT]. pp_binary([BS, $, | S], N, N0, Ind) -> Len = length(BS) + 1, case N - Len of N1 when N1 < 0 -> [$\n, Ind, BS, $, | pp_binary(S, N0 - Len, N0, Ind)]; N1 -> [BS, $, | pp_binary(S, N1, N0, Ind)] end; pp_binary([BS1, $:, BS2]=S, N, _N0, Ind) when length(BS1) + length(BS2) + 1 > N -> [$\n, Ind, S]; pp_binary(S, N, _N0, Ind) -> case iolist_size(S) > N of true -> [$\n, Ind, S]; false -> S end. write({{tuple, _IsTagged, L}, _}) -> [${, write_list(L, $,), $}]; write({{list, L}, _}) -> [$[, write_list(L, $|), $]]; write({{record, [{Name,_} | L]}, _}) -> [Name, ${, write_fields(L), $}]; write({{bin, S}, _}) -> S; write({S, _}) -> S. write_fields([]) -> ""; write_fields({dots, _}) -> "..."; write_fields([F | Fs]) -> [write_field(F) | write_fields_tail(Fs)]. write_fields_tail([]) -> ""; write_fields_tail({dots, _}) -> ",..."; write_fields_tail([F | Fs]) -> [$,, write_field(F) | write_fields_tail(Fs)]. write_field({{field, Name, _NameL, F}, _}) -> [Name, " = " | write(F)]. write_list({dots, _}, _S) -> "..."; write_list([E | Es], S) -> [write(E) | write_tail(Es, S)]. write_tail([], _S) -> []; write_tail([E | Es], S) -> [$,, write(E) | write_tail(Es, S)]; write_tail({dots, _}, S) -> [S | "..."]; write_tail(E, S) -> [S | write(E)]. %% The depth (D) is used for extracting and counting the characters to %% print. The structure is kept so that the returned intermediate %% format can be formatted. The separators (list, tuple, record) are %% counted but need to be added later. %% D =/= 0 print_length([], _D, _RF, _Enc, _Str) -> {"[]", 2}; print_length({}, _D, _RF, _Enc, _Str) -> {"{}", 2}; print_length(List, D, RF, Enc, Str) when is_list(List) -> case Str andalso printable_list(List, D, Enc) of true -> S = write_string(List, Enc), {S, length(S)}; %% Truncated lists could break some existing code. % {true, Prefix} -> % S = write_string(Prefix, Enc), % {[S | "..."], 3 + length(S)}; false -> print_length_list(List, D, RF, Enc, Str) end; print_length(Fun, _D, _RF, _Enc, _Str) when is_function(Fun) -> S = io_lib:write(Fun), {S, iolist_size(S)}; print_length(R, D, RF, Enc, Str) when is_atom(element(1, R)), is_function(RF) -> case RF(element(1, R), tuple_size(R) - 1) of no -> print_length_tuple(R, D, RF, Enc, Str); RDefs -> print_length_record(R, D, RF, RDefs, Enc, Str) end; print_length(Tuple, D, RF, Enc, Str) when is_tuple(Tuple) -> print_length_tuple(Tuple, D, RF, Enc, Str); print_length(<<>>, _D, _RF, _Enc, _Str) -> {"<<>>", 4}; print_length(<<_/bitstring>>, 1, _RF, _Enc, _Str) -> {"<<...>>", 7}; print_length(<<_/bitstring>>=Bin, D, _RF, Enc, Str) -> case bit_size(Bin) rem 8 of 0 -> D1 = D - 1, case Str andalso printable_bin(Bin, D1, Enc) of {true, List} when is_list(List) -> S = io_lib:write_string(List, $"), %" {[$<,$<,S,$>,$>], 4 + length(S)}; {false, List} when is_list(List) -> S = io_lib:write_string(List, $"), %" {[$<,$<,S,"/utf8>>"], 9 + length(S)}; {true, true, Prefix} -> S = io_lib:write_string(Prefix, $"), %" {[$<,$<, S | "...>>"], 7 + length(S)}; {false, true, Prefix} -> S = io_lib:write_string(Prefix, $"), %" {[$<,$<, S | "/utf8...>>"], 12 + length(S)}; false -> S = io_lib:write(Bin, D), {{bin,S}, iolist_size(S)} end; _ -> S = io_lib:write(Bin, D), {{bin,S}, iolist_size(S)} end; print_length(Term, _D, _RF, _Enc, _Str) -> S = io_lib:write(Term), {S, lists:flatlength(S)}. print_length_tuple(_Tuple, 1, _RF, _Enc, _Str) -> {"{...}", 5}; print_length_tuple(Tuple, D, RF, Enc, Str) -> L = print_length_list1(tuple_to_list(Tuple), D, RF, Enc, Str), IsTagged = is_atom(element(1, Tuple)) and (tuple_size(Tuple) > 1), {{tuple,IsTagged,L}, list_length(L, 2)}. print_length_record(_Tuple, 1, _RF, _RDefs, _Enc, _Str) -> {"{...}", 5}; print_length_record(Tuple, D, RF, RDefs, Enc, Str) -> Name = [$# | io_lib:write_atom(element(1, Tuple))], NameL = length(Name), Elements = tl(tuple_to_list(Tuple)), L = print_length_fields(RDefs, D - 1, Elements, RF, Enc, Str), {{record, [{Name,NameL} | L]}, list_length(L, NameL + 2)}. print_length_fields([], _D, [], _RF, _Enc, _Str) -> []; print_length_fields(_, 1, _, _RF, _Enc, _Str) -> {dots, 3}; print_length_fields([Def | Defs], D, [E | Es], RF, Enc, Str) -> [print_length_field(Def, D - 1, E, RF, Enc, Str) | print_length_fields(Defs, D - 1, Es, RF, Enc, Str)]. print_length_field(Def, D, E, RF, Enc, Str) -> Name = io_lib:write_atom(Def), {S, L} = print_length(E, D, RF, Enc, Str), NameL = length(Name) + 3, {{field, Name, NameL, {S, L}}, NameL + L}. print_length_list(List, D, RF, Enc, Str) -> L = print_length_list1(List, D, RF, Enc, Str), {{list, L}, list_length(L, 2)}. print_length_list1([], _D, _RF, _Enc, _Str) -> []; print_length_list1(_, 1, _RF, _Enc, _Str) -> {dots, 3}; print_length_list1([E | Es], D, RF, Enc, Str) -> [print_length(E, D - 1, RF, Enc, Str) | print_length_list1(Es, D - 1, RF, Enc, Str)]; print_length_list1(E, D, RF, Enc, Str) -> print_length(E, D - 1, RF, Enc, Str). list_length([], Acc) -> Acc; list_length([{_, Len} | Es], Acc) -> list_length_tail(Es, Acc + Len); list_length({_, Len}, Acc) -> Acc + Len. list_length_tail([], Acc) -> Acc; list_length_tail([{_,Len} | Es], Acc) -> list_length_tail(Es, Acc + 1 + Len); list_length_tail({_, Len}, Acc) -> Acc + 1 + Len. %% ?CHARS printable characters has depth 1. -define(CHARS, 4). printable_list(_L, 1, _Enc) -> false; printable_list(L, _D, latin1) -> io_lib:printable_latin1_list(L); printable_list(L, _D, _Uni) -> io_lib:printable_list(L). printable_bin(Bin, D, Enc) when D >= 0, ?CHARS * D =< byte_size(Bin) -> printable_bin(Bin, erlang:min(?CHARS * D, byte_size(Bin)), D, Enc); printable_bin(Bin, D, Enc) -> printable_bin(Bin, byte_size(Bin), D, Enc). printable_bin(Bin, Len, D, latin1) -> N = erlang:min(20, Len), L = binary_to_list(Bin, 1, N), case printable_latin1_list(L, N) of all when N =:= byte_size(Bin) -> {true, L}; all when N =:= Len -> % N < byte_size(Bin) {true, true, L}; all -> case printable_bin1(Bin, 1 + N, Len - N) of 0 when byte_size(Bin) =:= Len -> {true, binary_to_list(Bin)}; NC when D > 0, Len - NC >= D -> {true, true, binary_to_list(Bin, 1, Len - NC)}; NC when is_integer(NC) -> false end; NC when is_integer(NC), D > 0, N - NC >= D -> {true, true, binary_to_list(Bin, 1, N - NC)}; NC when is_integer(NC) -> false end; printable_bin(Bin, Len, D, _Uni) -> case valid_utf8(Bin,Len) of true -> case printable_unicode(Bin, Len, [], io:printable_range()) of {_, <<>>, L} -> {byte_size(Bin) =:= length(L), L}; {NC, Bin1, L} when D > 0, Len - NC >= D -> {byte_size(Bin)-byte_size(Bin1) =:= length(L), true, L}; {_NC, _Bin, _L} -> false end; false -> printable_bin(Bin, Len, D, latin1) end. printable_bin1(_Bin, _Start, 0) -> 0; printable_bin1(Bin, Start, Len) -> N = erlang:min(10000, Len), L = binary_to_list(Bin, Start, Start + N - 1), case printable_latin1_list(L, N) of all -> printable_bin1(Bin, Start + N, Len - N); NC when is_integer(NC) -> Len - (N - NC) end. %% -> all | integer() >=0. Adopted from io_lib.erl. % printable_latin1_list([_ | _], 0) -> 0; printable_latin1_list([C | Cs], N) when C >= $\s, C =< $~ -> printable_latin1_list(Cs, N - 1); printable_latin1_list([C | Cs], N) when C >= $\240, C =< $\377 -> printable_latin1_list(Cs, N - 1); printable_latin1_list([$\n | Cs], N) -> printable_latin1_list(Cs, N - 1); printable_latin1_list([$\r | Cs], N) -> printable_latin1_list(Cs, N - 1); printable_latin1_list([$\t | Cs], N) -> printable_latin1_list(Cs, N - 1); printable_latin1_list([$\v | Cs], N) -> printable_latin1_list(Cs, N - 1); printable_latin1_list([$\b | Cs], N) -> printable_latin1_list(Cs, N - 1); printable_latin1_list([$\f | Cs], N) -> printable_latin1_list(Cs, N - 1); printable_latin1_list([$\e | Cs], N) -> printable_latin1_list(Cs, N - 1); printable_latin1_list([], _) -> all; printable_latin1_list(_, N) -> N. valid_utf8(<<>>,_) -> true; valid_utf8(_,0) -> true; valid_utf8(<<_/utf8, R/binary>>,N) -> valid_utf8(R,N-1); valid_utf8(_,_) -> false. printable_unicode(<<C/utf8, R/binary>>=Bin, I, L, Range) when I > 0 -> case printable_char(C,Range) of true -> printable_unicode(R, I - 1, [C | L],Range); false -> {I, Bin, lists:reverse(L)} end; printable_unicode(Bin, I, L,_) -> {I, Bin, lists:reverse(L)}. printable_char($\n,_) -> true; printable_char($\r,_) -> true; printable_char($\t,_) -> true; printable_char($\v,_) -> true; printable_char($\b,_) -> true; printable_char($\f,_) -> true; printable_char($\e,_) -> true; printable_char(C,latin1) -> C >= $\s andalso C =< $~ orelse C >= 16#A0 andalso C =< 16#FF; printable_char(C,unicode) -> C >= $\s andalso C =< $~ orelse C >= 16#A0 andalso C < 16#D800 orelse C > 16#DFFF andalso C < 16#FFFE orelse C > 16#FFFF andalso C =< 16#10FFFF. write_string(S, latin1) -> io_lib:write_latin1_string(S, $"); %" write_string(S, _Uni) -> io_lib:write_string(S, $"). %" %% Throw 'no_good' if the indentation exceeds half the line length %% unless there is room for M characters on the line. cind({_S, Len}, Col, Ll, M, Ind, LD, W) when Len < Ll - Col - LD, Len + W + LD =< M -> Ind; cind({{list,L}, _Len}, Col, Ll, M, Ind, LD, W) -> cind_list(L, Col + 1, Ll, M, Ind, LD, W + 1); cind({{tuple,true,L}, _Len}, Col, Ll, M, Ind, LD, W) -> cind_tag_tuple(L, Col, Ll, M, Ind, LD, W + 1); cind({{tuple,false,L}, _Len}, Col, Ll, M, Ind, LD, W) -> cind_list(L, Col + 1, Ll, M, Ind, LD, W + 1); cind({{record,[{_Name,NLen} | L]}, _Len}, Col, Ll, M, Ind, LD, W) -> cind_record(L, NLen, Col, Ll, M, Ind, LD, W + NLen + 1); cind({{bin,_S}, _Len}, _Col, _Ll, _M, Ind, _LD, _W) -> Ind; cind({_S, _Len}, _Col, _Ll, _M, Ind, _LD, _W) -> Ind. cind_tag_tuple([{_Tag,Tlen} | L], Col, Ll, M, Ind, LD, W) -> TagInd = Tlen + 2, Tcol = Col + TagInd, if Ind > 0, TagInd > Ind -> Col1 = Col + Ind, if M + Col1 =< Ll; Col1 =< Ll div 2 -> cind_tail(L, Col1, Tcol, Ll, M, Ind, LD, W + Tlen); true -> throw(no_good) end; M + Tcol < Ll; Tcol < Ll div 2 -> cind_list(L, Tcol, Ll, M, Ind, LD, W + Tlen + 1); true -> throw(no_good) end. cind_record([F | Fs], Nlen, Col0, Ll, M, Ind, LD, W0) -> Nind = Nlen + 1, {Col, W} = cind_rec(Nind, Col0, Ll, M, Ind, W0), FW = cind_field(F, Col, Ll, M, Ind, last_depth(Fs, LD), W), cind_fields_tail(Fs, Col, Col + FW, Ll, M, Ind, LD, W + FW); cind_record(_, _Nlen, _Col, _Ll, _M, Ind, _LD, _W) -> Ind. cind_fields_tail([{_, Len}=F | Fs], Col0, Col, Ll, M, Ind, LD, W) -> LD1 = last_depth(Fs, LD), ELen = 1 + Len, if LD1 =:= 0, ELen + 1 < Ll - Col, W + ELen + 1 =< M, ?ATM_FLD(F); LD1 > 0, ELen < Ll - Col - LD1, W + ELen + LD1 =< M, ?ATM_FLD(F) -> cind_fields_tail(Fs, Col0, Col + ELen, Ll, M, Ind, LD, W + ELen); true -> FW = cind_field(F, Col0, Ll, M, Ind, LD1, 0), cind_fields_tail(Fs, Col0, Col + FW, Ll, M, Ind, LD, FW) end; cind_fields_tail(_, _Col0, _Col, _Ll, _M, Ind, _LD, _W) -> Ind. cind_field({{field, _N, _NL, _F}, Len}=Fl, Col, Ll, M, _Ind, LD, W) when Len < Ll - Col - LD, Len + W + LD =< M -> if ?ATM_FLD(Fl) -> Len; true -> Ll end; cind_field({{field, _Name, NameL, F}, _Len}, Col0, Ll, M, Ind, LD, W0) -> {Col, W} = cind_rec(NameL, Col0, Ll, M, Ind, W0 + NameL), cind(F, Col, Ll, M, Ind, LD, W), Ll. cind_rec(RInd, Col0, Ll, M, Ind, W0) -> Nl = (Ind > 0) and (RInd > Ind), DCol = case Nl of true -> Ind; false -> RInd end, Col = Col0 + DCol, if M + Col =< Ll; Col =< Ll div 2 -> W = case Nl of true -> 0; false -> W0 end, {Col, W}; true -> throw(no_good) end. cind_list({dots, _}, _Col0, _Ll, _M, Ind, _LD, _W) -> Ind; cind_list([E | Es], Col0, Ll, M, Ind, LD, W) -> WE = cind_element(E, Col0, Ll, M, Ind, last_depth(Es, LD), W), cind_tail(Es, Col0, Col0 + WE, Ll, M, Ind, LD, W + WE). cind_tail([], _Col0, _Col, _Ll, _M, Ind, _LD, _W) -> Ind; cind_tail([{_, Len}=E | Es], Col0, Col, Ll, M, Ind, LD, W) -> LD1 = last_depth(Es, LD), ELen = 1 + Len, if LD1 =:= 0, ELen + 1 < Ll - Col, W + ELen + 1 =< M, ?ATM(E); LD1 > 0, ELen < Ll - Col - LD1, W + ELen + LD1 =< M, ?ATM(E) -> cind_tail(Es, Col0, Col + ELen, Ll, M, Ind, LD, W + ELen); true -> WE = cind_element(E, Col0, Ll, M, Ind, LD1, 0), cind_tail(Es, Col0, Col0 + WE, Ll, M, Ind, LD, WE) end; cind_tail({dots, _}, _Col0, _Col, _Ll, _M, Ind, _LD, _W) -> Ind; cind_tail({_, Len}=E, _Col0, Col, Ll, M, Ind, LD, W) when Len + 1 < Ll - Col - (LD + 1), Len + 1 + W + (LD + 1) =< M, ?ATM(E) -> Ind; cind_tail(E, _Col0, Col, Ll, M, Ind, LD, _W) -> cind(E, Col, Ll, M, Ind, LD + 1, 0). cind_element({_, Len}=E, Col, Ll, M, _Ind, LD, W) when Len < Ll - Col - LD, Len + W + LD =< M, ?ATM(E) -> Len; cind_element(E, Col, Ll, M, Ind, LD, W) -> cind(E, Col, Ll, M, Ind, LD, W), Ll. last_depth([_ | _], _LD) -> 0; last_depth(_, LD) -> LD + 1. while_fail([], _F, V) -> V; while_fail([A | As], F, V) -> try F(A) catch _ -> while_fail(As, F, V) end. indent(N) when is_integer(N), N > 0 -> chars($\s, N-1). indent(1, Ind) -> % Optimization of common case [$\s | Ind]; indent(4, Ind) -> % Optimization of common case S2 = [$\s, $\s], [S2, S2 | Ind]; indent(N, Ind) when is_integer(N), N > 0 -> [chars($\s, N) | Ind]. %% A deep version of string:chars/2 chars(_C, 0) -> []; chars(C, 2) -> [C, C]; chars(C, 3) -> [C, C, C]; chars(C, N) when (N band 1) =:= 0 -> S = chars(C, N bsr 1), [S | S]; chars(C, N) -> S = chars(C, N bsr 1), [C, S | S].