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%{
import java.io.*;
import java.util.StringTokenizer;
%}
%token ITEM
%token <sval> NAME
%token REPLACE
%token OVERRIDE
%token TERMINATOR
%token DONE
%type <sval> identifier
%type <ival> mode
%start defn
%%
defn : ITEM identifier mode DONE '\n'
{
System.out.println( "Item definition" );
System.out.println( " Name = " + $2 );
System.out.println( " mode = " + $3 );
}
identifier : NAME { $$ = $1; }
mode : /* empty */ { $$ = OVERRIDE; }
| REPLACE { $$ = REPLACE; }
| OVERRIDE { $$ = OVERRIDE; }
;
%%
// Code cut from the byacc demo page and modified to take
// first arg as input file name
String ins;
StringTokenizer st;
void yyerror(String s)
{
System.out.println("par:"+s);
}
boolean newline;
int yylex()
{
String s;
int tok;
String tokstr;
Double d;
//System.out.print("yylex ");
if (!st.hasMoreTokens())
if (!newline)
{
newline=true;
System.out.println("tok: \\n");
return '\n'; //So we look like classic YACC example
}
else
return 0;
s = st.nextToken();
try {
if ( s.equalsIgnoreCase("ITEM") ) {
tok = ITEM;
System.out.println("tok: ITEM");
} else if ( s.equalsIgnoreCase("REPLACE") ) {
tok = REPLACE;
System.out.println("tok: REPLACE");
} else if ( s.equalsIgnoreCase("DONE") ) {
tok = DONE;
System.out.println("tok: DONE");
} else if ( s.equalsIgnoreCase("OVERRIDE")) {
tok = OVERRIDE;
System.out.println("tok: OVERRIDE");
} else {
yylval = new parserval( s );
tok = NAME;
System.out.println("tok: NAME -> " + s);
}
} catch ( Throwable e ) {
return 0;
}
return tok;
}
void dotest( String filepath ) throws java.io.FileNotFoundException
{
BufferedReader in = new BufferedReader(new FileReader(filepath));
// AS per the calculator demo
System.out.println("Note: you will need to separate the items");
System.out.println("with spaces, i.e.: 'ITEM hello override");
while (true)
{
System.out.print("example item:");
try
{
ins = in.readLine();
}
catch (Exception e)
{
}
st = new StringTokenizer(ins);
newline=false;
yyparse();
}
}
public static void main(String args[]) throws
java.io.FileNotFoundException
{
parser par = new parser();
par.yydebug = true;
System.out.println( "parse input file: " + args[0] );
par.dotest(args[0]);
}
// Invoke this code with
// java parser test.input
// where test.input is the file containing the input text
|
