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/* Calculate an expression read from stdin or from the arguments passed to
* the program (using stringstream's)
*/
#include <iostream>
#include <sstream>
#include "antlr/AST.hpp"
#include "CalcLexer.hpp"
#include "CalcParser.hpp"
#include "CalcTreeWalker.hpp"
int main( int argc, char* argv[] )
{
ANTLR_USING_NAMESPACE(std)
ANTLR_USING_NAMESPACE(antlr)
try
{
ostringstream expr;
istringstream input_string;
istream *input = &cin;
const char *filename = "<cin>";
if( argc > 1 )
{
// write the argv strings to a ostringstream...
for( int i = 1; i < argc; i++ )
{
if( i > 1 && i != (argc-1))
expr << ' ';
expr << argv[i];
}
input_string.str(expr.str());
input = &input_string;
filename = "<arguments>";
}
CalcLexer lexer(*input);
lexer.setFilename(filename);
CalcParser parser(lexer);
parser.setFilename(filename);
ASTFactory ast_factory;
parser.initializeASTFactory(ast_factory);
parser.setASTFactory(&ast_factory);
// Parse the input expression
parser.expr();
RefAST t = parser.getAST();
if( t )
{
// Print the resulting tree out in LISP notation
cout << t->toStringTree() << endl;
CalcTreeWalker walker;
// Traverse the tree created by the parser
float r = walker.expr(t);
cout << "value is " << r << endl;
}
else
cout << "No tree produced" << endl;
}
catch(ANTLRException& e)
{
cerr << "Parse exception: " << e.toString() << endl;
return -1;
}
catch(exception& e)
{
cerr << "exception: " << e.what() << endl;
return -1;
}
return 0;
}
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