%% =====================================================================
%% This library is free software; you can redistribute it and/or modify
%% it under the terms of the GNU Lesser General Public License as
%% published by the Free Software Foundation; either version 2 of the
%% License, or (at your option) any later version.
%%
%% This library is distributed in the hope that it will be useful, but
%% WITHOUT ANY WARRANTY; without even the implied warranty of
%% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
%% Lesser General Public License for more details.
%%
%% You should have received a copy of the GNU Lesser General Public
%% License along with this library; if not, write to the Free Software
%% Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
%% USA
%%
%% @private
%% @copyright 2001-2005 Richard Carlsson
%% @author Richard Carlsson <[email protected]>
%% @see edoc
%% @end
%% =====================================================================
%% @doc EDoc macro expansion
-module(edoc_macros).
-export([expand_tags/3, std_macros/1, check_defs/1]).
-import(edoc_report, [report/2, error/3, warning/4]).
-include("edoc.hrl").
-include("edoc_types.hrl").
-define(DEFAULT_XML_EXPORT, xmerl_html).
std_macros(Env) ->
(if Env#env.module =:= [] -> [];
true -> [{module, atom_to_list(Env#env.module)}]
end
++
if Env#env.package =:= [] -> [];
true -> [{package, atom_to_list(Env#env.package)}]
end
++
[{date, fun date_macro/3},
{docRoot, Env#env.root},
{link, fun link_macro/3},
{section, fun section_macro/3},
{time, fun time_macro/3},
{type, fun type_macro/3},
{version, fun version_macro/3}]).
%% Check well-formedness of user-specified list of macro definitions.
check_defs([{K, D} | Ds]) when is_atom(K), is_list(D) ->
check_defs(Ds);
check_defs([X | _Ds]) ->
report("bad macro definition: ~P.", [X, 10]),
exit(error);
check_defs([]) ->
ok.
%% Code for special macros should throw {error, Line, Reason} for error
%% reporting, where Reason and Line are passed to edoc_report:error(...)
%% together with the file name etc. The expanded text must be flat!
date_macro(_S, _Line, _Env) ->
edoc_lib:datestr(date()).
time_macro(_S, _Line, _Env) ->
edoc_lib:timestr(time()).
version_macro(S, Line, Env) ->
date_macro(S, Line, Env)
++ " " ++ time_macro(S, Line, Env).
link_macro(S, Line, Env) ->
{S1, S2} = edoc_lib:split_at_stop(S),
Ref = edoc_parser:parse_ref(S1, Line),
URI = edoc_refs:get_uri(Ref, Env),
Txt = if S2 =:= [] -> "<code>" ++ S1 ++ "</code>";
true -> S2
end,
Target = case edoc_refs:is_top(Ref, Env) of
true -> " target=\"_top\""; % note the initial space
false -> ""
end,
lists:flatten(io_lib:fwrite("<a href=\"~s\"~s>~s</a>",
[URI, Target, Txt])).
section_macro(S, _Line, _Env) ->
S1 = lists:reverse(edoc_lib:strip_space(
lists:reverse(edoc_lib:strip_space(S)))),
lists:flatten(io_lib:format("<a href=\"#~s\">~s</a>",
[edoc_lib:to_label(S1), S1])).
type_macro(S, Line, Env) ->
S1 = "t()=" ++ S,
Def = edoc_parser:parse_typedef(S1, Line),
{#t_typedef{type = T}, _} = Def,
Txt = edoc_layout:type(edoc_data:type(T, Env)),
lists:flatten(io_lib:fwrite("<code>~s</code>", [Txt])).
%% Expand inline macros in tag content.
expand_tags(Ts, Env, Where) ->
Defs = dict:from_list(lists:reverse(Env#env.macros)),
expand_tags(Ts, Defs, Env, Where).
expand_tags([#tag{data = Cs, line = L} = T | Ts], Defs, Env, Where) ->
[T#tag{data = expand_tag(Cs, L, Defs, Env, Where)}
| expand_tags(Ts, Defs, Env, Where)];
expand_tags([T | Ts], Defs, Env, Where) ->
[T | expand_tags(Ts, Defs, Env, Where)];
expand_tags([], _, _, _) ->
[].
expand_tag(Cs, L, Defs, Env, Where) ->
case catch {ok, expand_text(Cs, L, Defs, Env, Where)} of
{ok, Cs1} ->
lists:reverse(Cs1);
{'EXIT', R} ->
exit(R);
{error, L1, Error} ->
error(L1, Where, Error),
exit(error);
Other ->
throw(Other)
end.
%% Expand macros in arbitrary lines of text.
%% The result is in reverse order.
-record(state, {where, env, seen}).
expand_text(Cs, L, Defs, Env, Where) ->
St = #state{where = Where,
env = Env,
seen = sets:new()},
expand(Cs, L, Defs, St, []).
%% Inline macro syntax: "{@name content}"
%% where 'content' is optional, and separated from 'name' by one or
%% more whitespace characters. The content is bound to the '{@?}'
%% parameter variable, and the macro definition is expanded and
%% substituted for the call. Recursion is detected and reported as an
%% error, since there are (currently) no control flow operators.
%% Escape sequences:
%% "@{" -> "{"
%% "@}" -> "}"
%% "@@" -> "@"
expand([$@, $@ | Cs], L, Defs, St, As) ->
expand(Cs, L, Defs, St, [$@ | As]);
expand([$@, ${ | Cs], L, Defs, St, As) ->
expand(Cs, L, Defs, St, [${ | As]);
expand([$@, $} | Cs], L, Defs, St, As) ->
expand(Cs, L, Defs, St, [$} | As]);
expand([${, $@ | Cs], L, Defs, St, As) ->
expand_macro(Cs, L, Defs, St, As);
expand([$\n = C | Cs], L, Defs, St, As) ->
expand(Cs, L + 1, Defs, St, [C | As]);
expand([C | Cs], L, Defs, St, As) ->
expand(Cs, L, Defs, St, [C | As]);
expand([], _, _, _, As) ->
As.
expand_macro(Cs, L, Defs, St, As) ->
{M, Cs1, L1} = macro_name(Cs, L),
{Arg, Cs2, L2} = macro_content(Cs1, L1),
As1 = expand_macro_def(M, Arg, L, Defs, St, As),
expand(Cs2, L2, Defs, St, As1).
%% The macro argument (the "content") is expanded in the environment of
%% the call, and the result is bound to the '{@?}' parameter. The result
%% of the macro expansion is then expanded again. This allows macro
%% definitions to contain calls to other macros, avoids name capture of
%% '{@?}', and makes it easier to write handler functions for special
%% macros such as '{@link ...}', since the argument is already expanded.
expand_macro_def(M, Arg, L, Defs, St, As) ->
Seen = St#state.seen,
case sets:is_element(M, Seen) of
true ->
throw_error(L, {"recursive macro expansion of {@~s}.",
[M]});
false ->
Arg1 = lists:reverse(expand(Arg, L, Defs, St, [])),
Defs1 = dict:store('?', Arg1, Defs),
St1 = St#state{seen = sets:add_element(M, Seen)},
case dict:find(M, Defs) of
{ok, Def} ->
Txt = if is_function(Def) ->
Def(Arg1, L, St1#state.env);
is_list(Def) ->
Def
end,
expand(Txt, L, Defs1, St1, As);
error ->
warning(L, St1#state.where,
"undefined macro {@~s}.", [M]),
"??"
end
end.
%% The macro name ends at the first whitespace or '}' character. The
%% content, if any, starts at the next non-whitespace character.
%% See edoc_tags:scan_tag/is_name/1 for details on what is a valid
%% name. In macro names we also allow '?' as the initial character.
macro_name(Cs, L) ->
macro_name(Cs, [], L).
macro_name([C | Cs], As, L) when C >= $a, C =< $z ->
macro_name_1(Cs, [C | As], L);
macro_name([C | Cs], As, L) when C >= $A, C =< $Z ->
macro_name_1(Cs, [C | As], L);
macro_name([C | Cs], As, L) when C >= $\300, C =< $\377,
C =/= $\327, C =/= $\367 ->
macro_name_1(Cs, [C | As], L);
macro_name([$_ | Cs], As, L) ->
macro_name_1(Cs, [$_ | As], L);
macro_name([$? | Cs], As, L) ->
macro_name_1(Cs, [$? | As], L);
macro_name([$\s | _Cs], _As, L) ->
throw_error(L, macro_name);
macro_name([$\t | _Cs], _As, L) ->
throw_error(L, macro_name);
macro_name([$\n | _Cs], _As, L) ->
throw_error(L, macro_name);
macro_name([C | _Cs], As, L) ->
throw_error(L, {macro_name, [C | As]});
macro_name([], _As, L) ->
throw_error(L, macro_name).
macro_name_1([C | Cs], As, L) when C >= $a, C =< $z ->
macro_name_1(Cs, [C | As], L);
macro_name_1([C | Cs], As, L) when C >= $A, C =< $Z ->
macro_name_1(Cs, [C | As], L);
macro_name_1([C | Cs], As, L) when C >= $0, C =< $9 ->
macro_name_1(Cs, [C | As], L);
macro_name_1([C | Cs], As, L) when C >= $\300, C =< $\377,
C =/= $\327, C =/= $\367 ->
macro_name_1(Cs, [C | As], L);
macro_name_1([$_ | Cs], As, L) ->
macro_name_1(Cs, [$_ | As], L);
macro_name_1([$\s | Cs], As, L) ->
macro_name_2(Cs, As, L);
macro_name_1([$\t | Cs], As, L) ->
macro_name_2(Cs, As, L);
macro_name_1([$\n | Cs], As, L) ->
macro_name_2(Cs, As, L + 1);
macro_name_1([$} | _] = Cs, As, L) ->
macro_name_3(Cs, As, L);
macro_name_1([C | _Cs], As, L) ->
throw_error(L, {macro_name, [C | As]});
macro_name_1([], _As, L) ->
throw_error(L, unterminated_macro).
macro_name_2([$\s | Cs], As, L) ->
macro_name_2(Cs, As, L);
macro_name_2([$\t | Cs], As, L) ->
macro_name_2(Cs, As, L);
macro_name_2([$\n | Cs], As, L) ->
macro_name_2(Cs, As, L + 1);
macro_name_2([_ | _] = Cs, As, L) ->
macro_name_3(Cs, As, L);
macro_name_2([], _As, L) ->
throw_error(L, unterminated_macro).
macro_name_3(Cs, As, L) ->
{list_to_atom(lists:reverse(As)), Cs, L}.
%% The macro content ends at the first non-escaped '}' character that is
%% not balanced by a corresponding non-escaped '{@' sequence.
%% Escape sequences are those defined above.
macro_content(Cs, L) ->
%% If there is an error, we report the start line, not the end line.
case catch {ok, macro_content(Cs, [], L, 0)} of
{ok, X} ->
X;
{'EXIT', R} ->
exit(R);
'end' ->
throw_error(L, unterminated_macro);
Other ->
throw(Other)
end.
%% @throws 'end'
macro_content([$@, $@ | Cs], As, L, N) ->
macro_content(Cs, [$@, $@ | As], L, N); % escaped '@'
macro_content([$@, $} | Cs], As, L, N) ->
macro_content(Cs, [$}, $@ | As], L, N); % escaped '}'
macro_content([$@, ${ | Cs], As, L, N) ->
macro_content(Cs, [${, $@ | As], L, N); % escaped '{'
macro_content([${, $@ | Cs], As, L, N) ->
macro_content(Cs, [$@, ${ | As], L, N + 1);
macro_content([$} | Cs], As, L, 0) ->
{lists:reverse(As), Cs, L};
macro_content([$} | Cs], As, L, N) ->
macro_content(Cs, [$} | As], L, N - 1);
macro_content([$\n = C | Cs], As, L, N) ->
macro_content(Cs, [C | As], L + 1, N);
macro_content([C | Cs], As, L, N) ->
macro_content(Cs, [C | As], L, N);
macro_content([], _As, _L, _N) ->
throw('end').
-type line() :: erl_scan:line().
-type err() :: 'unterminated_macro'
| 'macro_name'
| {'macro_name', string()}
| {string(), [string()]}.
-spec throw_error(line(), err()) -> no_return().
throw_error(L, unterminated_macro) ->
throw_error(L, {"unexpected end of macro.", []});
throw_error(L, macro_name) ->
throw_error(L, {"missing macro name.", []});
throw_error(L, {macro_name, S}) ->
throw_error(L, {"bad macro name: '@~s...'.", [lists:reverse(S)]});
throw_error(L, D) ->
throw({error, L, D}).
