-#include <stdexcept>
-#include <sstream>
-#include "parser.hpp"
-#include "lexer.hpp"
-#include "debug.hpp"
+/** @file parser.cpp
+ *
+ * Implementation of GiNaC's parser. */
+
+/*
+ * GiNaC Copyright (C) 1999-2009 Johannes Gutenberg University Mainz, Germany
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "parser.h"
+#include "lexer.h"
+#include "debug.h"
#include "mul.h"
#include "constant.h"
+#include "function.h"
-namespace GiNaC
-{
+#include <sstream>
+#include <stdexcept>
+
+namespace GiNaC {
/// identifier_expr: identifier | identifier '(' expression* ')'
ex parser::parse_identifier_expr()
Parse_error_("no function \"" << name << "\" with " <<
args.size() << " arguments");
}
- ex ret = reader->second(args);
+ ex ret = GiNaC::function((unsigned)reader->second, args);
return ret;
}
}
extern numeric* _num_1_p;
+extern ex _ex0;
/// unary_expr: [+-] expression
-ex parser::parse_unary_expr(const int s)
+ex parser::parse_unary_expr()
{
- // consume '-' (or '+')
- get_next_tok();
- ex v = parse_expression();
- switch (s) {
- case '-':
- return (new mul(v, *_num_1_p))->setflag(status_flags::dynallocated);
- case '+':
- return v;
- default:
- Parse_error_("invalid unary operator \"" << char(s) << "\"");
- }
+ // Unlike most other parse_* method this one does NOT consume
+ // current token so parse_binop_rhs() knows what kind of operator
+ // is being parsed.
+
+ // There are different kinds of expressions which need to be handled:
+ // -a+b
+ // -(a)
+ // +a
+ // +(a)
+ // Delegete the work to parse_binop_rhs(), otherwise we end up
+ // duplicating it here.
+ ex lhs = _ex0; // silly trick
+ ex e = parse_binop_rhs(0, lhs);
+ return e;
}
/// primary: identifier_expr | number_expr | paren_expr | unary_expr
case '(':
return parse_paren_expr();
case '-':
- return parse_unary_expr('-');
case '+':
- return parse_unary_expr('+');
+ return parse_unary_expr();
case lexer::token_type::literal:
return parse_literal_expr();
case lexer::token_type::eof:
/// literal_expr: 'I' | 'Pi' | 'Euler' | 'Catalan'
ex parser::parse_literal_expr()
{
+ get_next_tok(); // consume the literal
if (scanner->str == "I")
return I;
else if (scanner->str == "Pi")
scanner->switch_input(&input);
get_next_tok();
ex ret = parse_expression();
+ // parse_expression() stops if it encounters an unknown token.
+ // This is not a bug: since the parser is recursive checking
+ // whether the next token is valid is responsibility of the caller.
+ // Hence make sure nothing is left in the stream:
+ if (token != lexer::token_type::eof)
+ Parse_error("expected EOF");
+
return ret;
}
return token;
}
-parser::parser(const symtab& syms_, const prototype_table& funcs_,
- const bool strict_) : strict(strict_), funcs(funcs_),
- syms(syms_)
+parser::parser(const symtab& syms_, const bool strict_,
+ const prototype_table& funcs_) : strict(strict_),
+ funcs(funcs_), syms(syms_)
{
scanner = new lexer();
}