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/*
* Different version of the calculator which parses the command line arguments.
* To do this the argv[] strings are first written to a ostringstream then
* a istringstream is constructed with the string from the ostringstream and
* fed to the lexer.
*/
#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);
if( argc == 1 )
{
cerr << argv[0] << ": <expression>" << endl;
return 1;
}
// write the argv strings to a ostringstream...
ostringstream expr;
for( int i = 1; i < argc; i++ )
{
if( i > 1 && i != (argc-1))
expr << ' ';
expr << argv[i];
}
istringstream input(expr.str());
try
{
CalcLexer lexer(input);
lexer.setFilename("<arguments>");
CalcParser parser(lexer);
parser.setFilename("<arguments>");
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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