Value expression architecture is now rewritten, but the functionality of the

old system (for example, the meaning of 'a') has yet to be restored.  In the
new scheme, this will be done by definition a function outside of the value
expression logic, rather than the tight coupling between journal innards and
value expressions that occurred in 2.x.

1 files changed, 159 insertions, 0 deletions

diff --git a/expr.cc b/expr.cc
new file mode 100644
index 00000000..0319e243
--- /dev/null
+++ b/expr.cc
@@ -0,0 +1,159 @@
+/*
+ * Copyright (c) 2003-2008, John Wiegley.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ *
+ * - Redistributions in binary form must reproduce the above copyright
+ *   notice, this list of conditions and the following disclaimer in the
+ *   documentation and/or other materials provided with the distribution.
+ *
+ * - Neither the name of New Artisans LLC nor the names of its
+ *   contributors may be used to endorse or promote products derived from
+ *   this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "expr.h"
+#include "parser.h"
+#include "op.h"
+
+namespace ledger {
+
+std::auto_ptr<expr_t::parser_t> expr_t::parser;
+
+expr_t::expr_t()
+{
+  TRACE_CTOR(expr_t, "");
+}
+
+expr_t::expr_t(const expr_t& other) : ptr(other.ptr), str(other.str)
+{
+  TRACE_CTOR(expr_t, "copy");
+}
+
+expr_t::expr_t(const string& _str, const unsigned int flags) : str(_str)
+{
+  TRACE_CTOR(expr_t, "const string&");
+
+  if (! _str.empty())
+    ptr = parser->parse(str, flags);
+}
+
+  expr_t::expr_t(std::istream& in, const unsigned int flags)
+{
+  TRACE_CTOR(expr_t, "std::istream&");
+
+  ptr = parser->parse(in, flags);
+}
+
+expr_t::expr_t(const ptr_op_t& _ptr, const string& _str)
+  : ptr(_ptr), str(_str)
+{
+  TRACE_CTOR(expr_t, "const ptr_op_t&, const string&");
+}
+
+expr_t::~expr_t() throw()
+{
+  TRACE_DTOR(expr_t);
+}
+
+expr_t& expr_t::operator=(const expr_t& _expr)
+{
+  str = _expr.str;
+  ptr = _expr.ptr;
+  return *this;
+}
+
+void expr_t::parse(const string& _str, const unsigned int flags)
+{
+  if (! parser.get())
+    throw_(parse_error, "Value expression parser not initialized");
+
+  str = _str;
+  ptr = parser->parse(str, flags);
+}
+
+void expr_t::parse(std::istream& in, const unsigned int flags)
+{
+  if (! parser.get())
+    throw_(parse_error, "Value expression parser not initialized");
+
+  str = "<stream>";
+  ptr = parser->parse(in, flags);
+}
+
+void expr_t::compile(scope_t& scope)
+{
+  if (ptr.get())
+    ptr = ptr->compile(scope);
+}
+
+value_t expr_t::calc(scope_t& scope) const
+{
+  if (ptr.get())
+    return ptr->calc(scope);
+  return NULL_VALUE;
+}
+
+value_t expr_t::eval(const string& _expr, scope_t& scope)
+{
+  return expr_t(_expr).calc(scope);
+}
+
+void expr_t::print(std::ostream& out, scope_t& scope) const
+{
+  op_t::print_context_t context(scope);
+  ptr->print(out, context);
+}
+
+void expr_t::dump(std::ostream& out) const
+{
+  if (ptr)
+    ptr->dump(out, 0);
+}
+
+void expr_t::read(std::ostream& in)
+{
+  if (ptr)
+    ptr->read(in);
+}
+
+void expr_t::read(const char *& data)
+{
+  if (ptr)
+    ptr->read(data);
+}
+
+void expr_t::write(std::ostream& out) const
+{
+  if (ptr)
+    ptr->write(out);
+}
+
+void expr_t::initialize()
+{
+  parser.reset(new expr_t::parser_t);
+}
+
+void expr_t::shutdown()
+{
+  parser.reset();
+}
+
+} // namespace ledger