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module ec;
import system;
const
S_char = 0;
S_module = 1;
var
col : integer;
row : integer;
look : char;
sym : integer;
procedure Err0( s : array of char );
begin
system.writestring( "Error line " );
system.writeinteger( row );
system.writestring( ", pos " );
system.writeinteger( col );
system.writestring( ": " );
system.writeline( s );
end
(* TODO: segfault when defining parameter *)
procedure Err1N( s : array of char, n : integer );
begin
system.writestring( "Error line " );
system.writeinteger( row );
system.writestring( ", pos " );
system.writeinteger( col );
system.writestring( ": " );
system.writestring( s );
system.writestring( " " );
system.writeinteger( n );
end
procedure Halt;
begin
system.halt( 1 )
end
procedure Abort0( s : array of char );
begin
Err0( s );
Halt;
end
procedure Abort1N( s : array of char, n : integer );
begin
Err1N( s, n );
Halt;
end
(* scanner *)
procedure getChar : char;
var
c : char;
begin
c := system.readchar( );
if ( c = char( 0 ) ) do
return c;
end;
col := col + 1;
if ( c = char( 10 ) ) do
col := 1;
row := row + 1;
end;
return c;
end
procedure isWhite( c : char ) : boolean;
begin
if ( c = char( 0 ) ) or ( c = char( 10 ) ) or ( c = char( 13 ) ) or ( c = char( 9 ) ) do
return true
else
return false
end
end
procedure skipWhite;
begin
while ( isWhite( look ) ) do
look := getChar( );
end
end
procedure getSym : integer;
begin
skipWhite;
return S_char;
end
(* parser *)
procedure Expect( expect : integer );
begin
if ( sym = expect ) do
sym := getSym( );
else
(* TODO: symtable names
Abort( "Expected symbol", symname[expect] );
*)
Abort0( "Expected symbol" );
end
end
procedure init;
begin
col := 1;
row := 1;
look := getChar( );
sym := getSym( );
end
procedure prologue;
begin
system.writeline( "[bits 32]" );
system.writeline( "cpu 486" );
system.writeline( "org 0x1000000" );
end
procedure doModule;
begin
Expect( S_module );
(*
look := getChar( );
while ( look <> char( 0 ) ) do
if not isWhite( look ) do
system.writechar( look );
end;
look := getChar( );
end;
*)
end
procedure epilogue;
begin
system.writeline( "hlt" );
end
begin
prologue;
init;
doModule;
epilogue;
system.halt( 0 );
end
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