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486 | with Ada.Wide_Wide_Text_Io;
with Anagram.String_Sources;
with Anagram.Grammars.Scanners;
with Anagram.Grammars.Scanner_Handler;
with League.String_Vectors;
with Anagram.Grammars.Parser_Utils;
-- 3
with Ag.Goto_Table;
use Ag.Goto_Table;
with Ag_Tokens;
use Ag_Tokens;
with Ag.Shift_Reduce;
use Ag.Shift_Reduce;
package body Ag is
package Ag_Goto renames Ag.Goto_Table;
package Ag_Shift_Reduce renames Ag.Shift_Reduce;
function Grammar (Self : in out Parser) return Anagram.Grammars.Grammar is
begin
return Anagram.Grammars.Constructors.Complete (Self.Constructor);
end Grammar;
procedure Read
(Self : in out Parser;
Text : League.Strings.Universal_String;
Tail_List : Boolean := False)
is
Scanner : aliased Anagram.Grammars.Scanners.Scanner;
Handler : aliased Anagram.Grammars.Scanner_Handler.Handler;
Context : PU.Context_Node;
procedure yyerror (X : Wide_Wide_String) is
begin
Ada.Wide_Wide_Text_IO.Put_Line
(X & " on line" & Positive'Wide_Wide_Image (Handler.Get_Line));
end;
function YYLex return Token is
Result : Token;
begin
Scanner.Get_Token (Result);
return Result;
end YYLex;
procedure YYParse is
-- Rename User Defined Packages to Internal Names.
package yy_goto_tables renames
Ag.Goto_Table;
package yy_shift_reduce_tables renames
Ag.Shift_Reduce;
package yy_tokens renames
Ag_Tokens;
use yy_tokens, yy_goto_tables, yy_shift_reduce_tables;
procedure yyerrok;
procedure yyclearin;
package yy is
-- the size of the value and state stacks
stack_size : constant Natural := 300;
-- subtype rule is natural;
subtype parse_state is natural;
-- subtype nonterminal is integer;
-- encryption constants
default : constant := -1;
first_shift_entry : constant := 0;
accept_code : constant := -3001;
error_code : constant := -3000;
-- stack data used by the parser
tos : natural := 0;
value_stack : array(0..stack_size) of yy_tokens.yystype;
state_stack : array(0..stack_size) of parse_state;
-- current input symbol and action the parser is on
action : integer;
rule_id : rule;
input_symbol : yy_tokens.token;
-- error recovery flag
error_flag : natural := 0;
-- indicates 3 - (number of valid shifts after an error occurs)
look_ahead : boolean := true;
index : integer;
-- Is Debugging option on or off
DEBUG : constant boolean := FALSE;
end yy;
function goto_state
(state : yy.parse_state;
sym : nonterminal) return yy.parse_state;
function parse_action
(state : yy.parse_state;
t : yy_tokens.token) return integer;
pragma inline(goto_state, parse_action);
function goto_state(state : yy.parse_state;
sym : nonterminal) return yy.parse_state is
index : integer;
begin
index := goto_offset(state);
while integer(goto_matrix(index).nonterm) /= sym loop
index := index + 1;
end loop;
return integer(goto_matrix(index).newstate);
end goto_state;
function parse_action(state : yy.parse_state;
t : yy_tokens.token) return integer is
index : integer;
tok_pos : integer;
default : constant integer := -1;
begin
tok_pos := yy_tokens.token'pos(t);
index := shift_reduce_offset(state);
while integer(shift_reduce_matrix(index).t) /= tok_pos and then
integer(shift_reduce_matrix(index).t) /= default
loop
index := index + 1;
end loop;
return integer(shift_reduce_matrix(index).act);
end parse_action;
-- error recovery stuff
procedure handle_error is
temp_action : integer;
begin
if yy.error_flag = 3 then -- no shift yet, clobber input.
if yy.debug then
Ada.Wide_Wide_Text_Io.Put_Line ("Ayacc.YYParse: Error Recovery Clobbers " &
yy_tokens.token'Wide_Wide_Image (yy.input_symbol));
end if;
if yy.input_symbol = yy_tokens.end_of_input then -- don't discard,
if yy.debug then
Ada.Wide_Wide_Text_IO.Put_Line ("Ayacc.YYParse: Can't discard END_OF_INPUT, quiting...");
end if;
raise yy_tokens.syntax_error;
end if;
yy.look_ahead := true; -- get next token
return; -- and try again...
end if;
if yy.error_flag = 0 then -- brand new error
yyerror("Syntax Error");
end if;
yy.error_flag := 3;
-- find state on stack where error is a valid shift --
if yy.debug then
Ada.Wide_Wide_Text_IO.Put_Line ("Ayacc.YYParse: Looking for state with error as valid shift");
end if;
loop
if yy.debug then
Ada.Wide_Wide_Text_IO.Put_Line ("Ayacc.YYParse: Examining State " &
yy.parse_state'Wide_Wide_Image (yy.state_stack(yy.tos)));
end if;
temp_action := parse_action(yy.state_stack(yy.tos), error);
if temp_action >= yy.first_shift_entry then
if yy.tos = yy.stack_size then
Ada.Wide_Wide_Text_IO.Put_Line (" Stack size exceeded on state_stack");
raise yy_Tokens.syntax_error;
end if;
yy.tos := yy.tos + 1;
yy.state_stack(yy.tos) := temp_action;
exit;
end if;
Decrement_Stack_Pointer :
begin
yy.tos := yy.tos - 1;
exception
when Constraint_Error =>
yy.tos := 0;
end Decrement_Stack_Pointer;
if yy.tos = 0 then
if yy.debug then
Ada.Wide_Wide_Text_IO.Put_Line ("Ayacc.YYParse: Error recovery popped entire stack, aborting...");
end if;
raise yy_tokens.syntax_error;
end if;
end loop;
if yy.debug then
Ada.Wide_Wide_Text_IO.Put_Line ("Ayacc.YYParse: Shifted error token in state " &
yy.parse_state'Wide_Wide_Image (yy.state_stack(yy.tos)));
end if;
end handle_error;
-- print debugging information for a shift operation
procedure shift_debug(state_id: yy.parse_state; lexeme: yy_tokens.token) is
begin
Ada.Wide_Wide_Text_IO.Put_Line ("Ayacc.YYParse: Shift "& yy.parse_state'Wide_Wide_Image (state_id)&" on input symbol "&
yy_tokens.token'Wide_Wide_Image (lexeme));
end;
-- print debugging information for a reduce operation
procedure reduce_debug(rule_id: rule; state_id: yy.parse_state) is
begin
Ada.Wide_Wide_Text_IO.Put_Line ("Ayacc.YYParse: Reduce by rule "&rule'Wide_Wide_Image (rule_id)&" goto state "&
yy.parse_state'Wide_Wide_Image (state_id));
end;
-- make the parser believe that 3 valid shifts have occured.
-- used for error recovery.
procedure yyerrok is
begin
yy.error_flag := 0;
end yyerrok;
-- called to clear input symbol that caused an error.
procedure yyclearin is
begin
-- yy.input_symbol := yylex;
yy.look_ahead := true;
end yyclearin;
begin
-- initialize by pushing state 0 and getting the first input symbol
yy.state_stack(yy.tos) := 0;
loop
yy.index := shift_reduce_offset(yy.state_stack(yy.tos));
if integer(shift_reduce_matrix(yy.index).t) = yy.default then
yy.action := integer(shift_reduce_matrix(yy.index).act);
else
if yy.look_ahead then
yy.look_ahead := false;
yy.input_symbol := yylex;
end if;
yy.action :=
parse_action(yy.state_stack(yy.tos), yy.input_symbol);
end if;
if yy.action >= yy.first_shift_entry then -- SHIFT
if yy.debug then
shift_debug(yy.action, yy.input_symbol);
end if;
-- Enter new state
if yy.tos = yy.stack_size then
Ada.Wide_Wide_Text_IO.Put_Line (" Stack size exceeded on state_stack");
raise yy_Tokens.syntax_error;
end if;
yy.tos := yy.tos + 1;
yy.state_stack(yy.tos) := yy.action;
yy.value_stack(yy.tos) := yylval;
if yy.error_flag > 0 then -- indicate a valid shift
yy.error_flag := yy.error_flag - 1;
end if;
-- Advance lookahead
yy.look_ahead := true;
elsif yy.action = yy.error_code then -- ERROR
handle_error;
elsif yy.action = yy.accept_code then
if yy.debug then
Ada.Wide_Wide_Text_IO.Put_Line ("Ayacc.YYParse: Accepting Grammar...");
end if;
exit;
else -- Reduce Action
-- Convert action into a rule
yy.rule_id := -1 * yy.action;
-- Execute User Action
-- user_action(yy.rule_id);
case yy.rule_id is
when 12 =>
--# line 72 "../ag.y"
Context.Add_Token (YY.Value_Stack (YY.TOS - 1).Image);
when 13 =>
--# line 75 "../ag.y"
Context.Add_Token (YY.Value_Stack (YY.TOS - 4).Image, YY.Value_Stack (YY.TOS - 2).Image, YY.Value_Stack (YY.TOS - 1).Image);
when 14 =>
--# line 79 "../ag.y"
Context.Add_With (YY.Value_Stack (YY.TOS - 1).Image);
when 15 =>
--# line 83 "../ag.y"
Context.Add_Non_Terminal (YY.Value_Stack (YY.TOS - 3).Image, YY.Value_Stack (YY.TOS - 1).Production_List);
when 16 =>
--# line 89 "../ag.y"
YYVal := (Production_List,
Context.New_Production_List (YY.Value_Stack (YY.TOS).Named_Production));
when 17 =>
--# line 95 "../ag.y"
YYVal := (Production_List,
Context.Add_Production (YY.Value_Stack (YY.TOS - 2).Production_List, YY.Value_Stack (YY.TOS).Named_Production));
when 18 =>
--# line 102 "../ag.y"
YYVal := (Named_Production,
Context.To_Named_Production (YY.Value_Stack (YY.TOS).Production, YY.Value_Stack (YY.TOS - 2).Image));
when 19 =>
--# line 108 "../ag.y"
YYVal := (Named_Production,
Context.To_Named_Production (YY.Value_Stack (YY.TOS).Production));
when 20 =>
--# line 115 "../ag.y"
YYVal := (Production, Context.New_Production (YY.Value_Stack (YY.TOS).Named_Part));
when 21 =>
--# line 118 "../ag.y"
YYVal := (Production, Context.Add_Part (YY.Value_Stack (YY.TOS - 1).Production, YY.Value_Stack (YY.TOS).Named_Part));
when 22 =>
--# line 122 "../ag.y"
YYVal := (Named_Part, Context.To_Named_Part (YY.Value_Stack (YY.TOS).Part));
when 23 =>
--# line 125 "../ag.y"
YYVal := (Named_Part, Context.To_Named_Part (YY.Value_Stack (YY.TOS - 3).Part, YY.Value_Stack (YY.TOS - 1).Image));
when 24 =>
--# line 129 "../ag.y"
YYVal := (Part, Context.Add_Reference (YY.Value_Stack (YY.TOS).Image));
when 25 =>
--# line 132 "../ag.y"
YYVal := (Part, Context.Add_List (YY.Value_Stack (YY.TOS - 1).Production_List));
when 26 =>
--# line 135 "../ag.y"
YYVal := (Part, Context.Add_Option ( YY.Value_Stack (YY.TOS - 1).Production_List));
when 30 =>
--# line 152 "../ag.y"
YYVal := (Kind => None);
Context.Add_Inherited_Attr
(Target => YY.Value_Stack (YY.TOS - 5).Vector,
Tipe => YY.Value_Stack (YY.TOS - 3).Image,
Names => YY.Value_Stack (YY.TOS - 1).Vector);
when 31 =>
--# line 163 "../ag.y"
YYVal := (Kind => None);
Context.Add_Synthesized_Attr
(Target => YY.Value_Stack (YY.TOS - 5).Vector,
Tipe => YY.Value_Stack (YY.TOS - 3).Image,
Names => YY.Value_Stack (YY.TOS - 1).Vector);
when 32 =>
--# line 174 "../ag.y"
YYVal := (Kind => None);
Context.Add_Local_Attr
(Target => YY.Value_Stack (YY.TOS - 5).Vector,
Tipe => YY.Value_Stack (YY.TOS - 3).Image,
Names => YY.Value_Stack (YY.TOS - 1).Vector);
when 34 =>
--# line 187 "../ag.y"
YYVal := (Kind => None);
Context.Add_Rule (YY.Value_Stack (YY.TOS - 4).Vector, YY.Value_Stack (YY.TOS - 1).Image);
when 35 =>
--# line 194 "../ag.y"
YYVal := (Image, Scanner.Get_Text);
when 36 =>
--# line 198 "../ag.y"
Context.Add_Priority (YY.Value_Stack (YY.TOS - 3).Image, YY.Value_Stack (YY.TOS - 2).Image, YY.Value_Stack (YY.TOS - 1).Image);
when 37 =>
--# line 204 "../ag.y"
YYVal := (Vector, League.String_Vectors.Empty_Universal_String_Vector);
YYVal.Vector.Append (YY.Value_Stack (YY.TOS).Image);
when 38 =>
--# line 210 "../ag.y"
YYVal :=(Vector, YY.Value_Stack (YY.TOS - 2).Vector);
YYVal.Vector.Append (YY.Value_Stack (YY.TOS).Image);
when 39 =>
--# line 217 "../ag.y"
YYVal := (Image, Scanner.Get_Text);
when 40 =>
--# line 221 "../ag.y"
YYVal := (Image, Scanner.Get_Text);
when others => null;
end case;
-- Pop RHS states and goto next state
yy.tos := yy.tos - rule_length(yy.rule_id) + 1;
if yy.tos > yy.stack_size then
Ada.Wide_Wide_Text_IO.Put_Line (" Stack size exceeded on state_stack");
raise yy_Tokens.syntax_error;
end if;
yy.state_stack(yy.tos) := goto_state(yy.state_stack(yy.tos-1) ,
get_lhs_rule(yy.rule_id));
yy.value_stack(yy.tos) := yyval;
if yy.debug then
reduce_debug(yy.rule_id,
goto_state(yy.state_stack(yy.tos - 1),
get_lhs_rule(yy.rule_id)));
end if;
end if;
end loop;
end yyparse;
Source : aliased Anagram.String_Sources.String_Source;
begin
Source.Create (Text);
Scanner.Set_Source (Source'Unchecked_Access);
Scanner.Set_Handler (Handler'Unchecked_Access);
YYParse;
Context.Complete (Self.Constructor, Tail_List);
end Read;
end Ag;
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