View Source otp_formatter (rebar3_format v1.3.0)
Rebar3 Pretty Printing of abstract Erlang syntax trees, based on original erl_prettypr.
It was taken verbatim from erl_prettypr and it was modified just to fix some bugs.
This module is a front end to the pretty-printing library moduleprettypr
, for text formatting of abstract syntax trees defined by the module erl_syntax
.
Link to this section Summary
Functions
Equivalent to best(Tree, []).
layout/2
function, except that here, the final layout has been selected with respect to the given options. The atom empty
is returned if no such layout could be produced. For information on the options, see the format/2
function.See also: best/1, format/2, layout/2, prettypr:best/3.
Equivalent to format(Tree, []).
.beam
file that has been compiled with debug_info
, the following should print the source code for the module (as it looks in the debug info representation): {ok,{_,[{abstract_code,{_,AC}}]}} =
beam_lib:chunks("myfile.beam",[abstract_code]),
io:put_chars(otp_formatter:format(erl_syntax:form_list(AC), [], #{}))
Available options:- {hook, none |
hook()
} - Unless the value is
none
, the given function is called for each node whose list of annotations is not empty; see below for details. The default value isnone
. - {paper, integer()}
- Specifies the preferred maximum number of characters on any line, including indentation. The default value is 80.
- {ribbon, integer()}
- Specifies the preferred maximum number of characters on any line, not counting indentation. The default value is 65.
- {user, term()}
- User-specific data for use in hook functions. The default value is
undefined
. - {encoding, epp:source_encoding()}
- Specifies the encoding of the generated file.
hook()
type) is passed the current syntax tree node, the context, and a continuation. The context can be examined and manipulated by functions such as get_ctxt_user/1
and set_ctxt_user/2
. The hook must return a "document" data structure (see layout/2
and best/2
); this may be constructed in part or in whole by applying the continuation function. For example, the following is a trivial hook: fun (Node, Ctxt, Cont) -> Cont(Node, Ctxt) end
which yields the same result as if no hook was given. The following, however: fun (Node, Ctxt, Cont) ->
Doc = Cont(Node, Ctxt),
prettypr:beside(prettypr:text("<b>"),
prettypr:beside(Doc,
prettypr:text("</b>")))
end
will place the text of any annotated node (regardless of the annotation data) between HTML "boldface begin" and "boldface end" tags.See also: erl_syntax, best/2, format/1, get_ctxt_user/1, layout/2, set_ctxt_user/2.
Opts
to configure the formatter.See also: set_ctxt_hook/2.
See also: set_ctxt_linewidth/2.
See also: set_ctxt_paperwidth/2.
See also: set_ctxt_precedence/2.
See also: set_ctxt_user/2.
Equivalent to layout(Tree, []).
Creates an abstract document layout for a syntax tree. The result represents a set of possible layouts (cf. module prettypr
). For information on the options, see format/2
; note, however, that the paper
and ribbon
options are ignored by this function.
See also: get_ctxt_hook/1.
Updates the line width field of the pretty-printer context.
Updates the paper width field of the pretty-printer context.
erl_parse
module for operator precedences.See also: //stdlib/erl_parse, get_ctxt_precedence/1.
See also: get_ctxt_user/1.
Link to this section Types
-type clause_t() :: case_expr | fun_expr | if_expr | maybe_expr | receive_expr | try_expr | {function, prettypr:document()} | spec.
-type context() :: #ctxt{}.
-type hook() :: none | fun((erl_syntax:syntaxTree(), _, _) -> prettypr:document()).
Link to this section Functions
-spec best(erl_syntax:syntaxTree()) -> empty | prettypr:document().
Equivalent to best(Tree, []).
-spec best(erl_syntax:syntaxTree(), [term()]) -> empty | prettypr:document().
layout/2
function, except that here, the final layout has been selected with respect to the given options. The atom empty
is returned if no such layout could be produced. For information on the options, see the format/2
function.See also: best/1, format/2, layout/2, prettypr:best/3.
-spec format(erl_syntax:syntaxTree()) -> string().
Equivalent to format(Tree, []).
-spec format(erl_syntax:syntaxTree(), [pos_integer()], rebar3_formatter:opts()) -> string().
.beam
file that has been compiled with debug_info
, the following should print the source code for the module (as it looks in the debug info representation): {ok,{_,[{abstract_code,{_,AC}}]}} =
beam_lib:chunks("myfile.beam",[abstract_code]),
io:put_chars(otp_formatter:format(erl_syntax:form_list(AC), [], #{}))
Available options:- {hook, none |
hook()
} - Unless the value is
none
, the given function is called for each node whose list of annotations is not empty; see below for details. The default value isnone
. - {paper, integer()}
- Specifies the preferred maximum number of characters on any line, including indentation. The default value is 80.
- {ribbon, integer()}
- Specifies the preferred maximum number of characters on any line, not counting indentation. The default value is 65.
- {user, term()}
- User-specific data for use in hook functions. The default value is
undefined
. - {encoding, epp:source_encoding()}
- Specifies the encoding of the generated file.
hook()
type) is passed the current syntax tree node, the context, and a continuation. The context can be examined and manipulated by functions such as get_ctxt_user/1
and set_ctxt_user/2
. The hook must return a "document" data structure (see layout/2
and best/2
); this may be constructed in part or in whole by applying the continuation function. For example, the following is a trivial hook: fun (Node, Ctxt, Cont) -> Cont(Node, Ctxt) end
which yields the same result as if no hook was given. The following, however: fun (Node, Ctxt, Cont) ->
Doc = Cont(Node, Ctxt),
prettypr:beside(prettypr:text("<b>"),
prettypr:beside(Doc,
prettypr:text("</b>")))
end
will place the text of any annotated node (regardless of the annotation data) between HTML "boldface begin" and "boldface end" tags.See also: erl_syntax, best/2, format/1, get_ctxt_user/1, layout/2, set_ctxt_user/2.
-spec format_file(file:filename_all(), nostate, rebar3_formatter:opts()) -> rebar3_formatter:result().
Opts
to configure the formatter.
See also: set_ctxt_hook/2.
-spec get_ctxt_linewidth(context()) -> integer().
See also: set_ctxt_linewidth/2.
-spec get_ctxt_paperwidth(context()) -> integer().
See also: set_ctxt_paperwidth/2.
-spec get_ctxt_precedence(context()) -> integer().
See also: set_ctxt_precedence/2.
-spec get_ctxt_user(context()) -> term().
See also: set_ctxt_user/2.
-spec init(rebar3_formatter:opts(), undefined | rebar_state:t()) -> nostate.
-spec layout(erl_syntax:syntaxTree()) -> prettypr:document().
Equivalent to layout(Tree, []).
-spec layout(erl_syntax:syntaxTree(), [term()]) -> prettypr:document().
Creates an abstract document layout for a syntax tree. The result represents a set of possible layouts (cf. module prettypr
). For information on the options, see format/2
; note, however, that the paper
and ribbon
options are ignored by this function.
prettypr
module, or used in a hook function (see format/2
for details).See also: prettypr, format/2, layout/1.
See also: get_ctxt_hook/1.
Updates the line width field of the pretty-printer context.
Note: changing this value (and passing the resulting context to a continuation function) does not affect the normal formatting, but may affect user-defined behaviour in hook functions.See also: get_ctxt_linewidth/1.
Updates the paper width field of the pretty-printer context.
Note: changing this value (and passing the resulting context to a continuation function) does not affect the normal formatting, but may affect user-defined behaviour in hook functions.See also: get_ctxt_paperwidth/1.
erl_parse
module for operator precedences.See also: //stdlib/erl_parse, get_ctxt_precedence/1.
See also: get_ctxt_user/1.