#ifndef MSP_DATAFILE_LOADER_H_
#define MSP_DATAFILE_LOADER_H_
-#include <fstream>
#include <map>
-#include "error.h"
+#include <msp/io/buffered.h>
+#include <msp/io/file.h>
+#include "except.h"
#include "parser.h"
#include "statement.h"
#include "value.h"
Loads a statement by calling a function that takes an array of values.
*/
template<typename L, typename A0>
-class LoaderFunc1<L, const std::
list<A0> &>: public LoaderAction
+class LoaderFunc1<L, const std::
vector<A0> &>: public LoaderAction
{
public:
- typedef void (L::*FuncType)(const std::
list<A0> &);
+ typedef void (L::*FuncType)(const std::
vector<A0> &);
LoaderFunc1(FuncType f): func(f) { }
void execute(Loader &l, const Statement &st) const
{
std::vector<A0> values;
values.reserve(st.args.size());
- for(ValueArray::iterator i=st.args.begin(); i!=st.args.end(); ++i)
+ for(ValueArray::const_iterator i=st.args.begin(); i!=st.args.end(); ++i)
values.push_back(i->get<A0>());
(dynamic_cast<L &>(l).*func)(values);
}
};
+template<typename L, typename A0, typename A1, typename A2, typename A3, typename A4>
+class LoaderFunc5: public LoaderAction
+{
+public:
+ typedef void (L::*FuncType)(A0, A1, A2, A3, A4);
+
+ LoaderFunc5(FuncType f): func(f) { }
+ void execute(Loader &l, const Statement &st) const
+ {
+ if(st.args.size()!=5) throw TypeError(st.get_location()+": Wrong number of arguments");
+ (dynamic_cast<L &>(l).*func)(st.args[0].get<A0>(), st.args[1].get<A1>(), st.args[2].get<A2>(), st.args[3].get<A3>(), st.args[4].get<A4>());
+ }
+private:
+ FuncType func;
+};
+
+
template<typename L, typename T0>
class LoadValue1: public LoaderAction
{
};
+template<typename L, typename T0>
+class LoadValue1<L, T0 *>: public LoaderAction
+{
+public:
+ typedef T0 *L::*Pointer0Type;
+
+ LoadValue1(Pointer0Type p0): ptr0(p0) { }
+ void execute(Loader &l, const Statement &st) const
+ {
+ if(st.args.size()!=1) throw TypeError(st.get_location()+": Wrong number of arguments");
+ typename L::Loader &ldr=dynamic_cast<typename L::Loader &>(l);
+ ldr.get_object().*ptr0=ldr.get_collection().template get<T0>(st.args[0].get<std::string>());
+ }
+private:
+ Pointer0Type ptr0;
+};
+
+
template<typename L, typename T0, typename T1>
class LoadValue2: public LoaderAction
{
/**
-Base class for data loaders. To enable objects of a certain class to be loaded
-from datafiles, create a public Loader class in it, derived from this class.
-Typically the Loader class contains a reference to the object being loaded. If
-you want to load data members of the object directly, the Loader class must
-have a member function get_object() returning that reference.
+Base class for data loaders. To give loading capabilities to a class, create a
+public Loader class in it, derived from this class. Typically a loader object
+contains a reference to the loaded object. To make use of loading directly
+into data members, the Loader class must have a get_object() member function,
+returning that reference. If direct loading of pointers is desired, the Loader
+class must also have a get_collection() member function, returning a collection
+to get pointers from.
*/
class Loader
{
protected:
Loader(): cur_st(0) { }
+ /**
+ Adds a keyword that is loaded with a zero-argument function.
+ */
template<typename L>
void add(const std::string &k, void (L::*func)())
- { actions.insert(typename ActionMap::value_type(k, new LoaderFunc0<L>(func))); }
+ { add(k, new LoaderFunc0<L>(func)); }
template<typename L, typename A0>
void add(const std::string &k, void (L::*func)(A0))
- { actions.insert(typename ActionMap::value_type(k, new LoaderFunc1<L, A0>(func))); }
+ { add(k, new LoaderFunc1<L, A0>(func)); }
template<typename L, typename A0, typename A1>
void add(const std::string &k, void (L::*func)(A0, A1))
- { actions.insert(typename ActionMap::value_type(k, new LoaderFunc2<L, A0, A1>(func))); }
+ { add(k, new LoaderFunc2<L, A0, A1>(func)); }
template<typename L, typename A0, typename A1, typename A2>
void add(const std::string &k, void (L::*func)(A0, A1, A2))
- { actions.insert(typename ActionMap::value_type(k, new LoaderFunc3<L, A0, A1, A2>(func))); }
+ { add(k, new LoaderFunc3<L, A0, A1, A2>(func)); }
template<typename L, typename A0, typename A1, typename A2, typename A3>
void add(const std::string &k, void (L::*func)(A0, A1, A2, A3))
- { actions.insert(typename ActionMap::value_type(k, new LoaderFunc4<L, A0, A1, A2, A3>(func))); }
+ { add(k, new LoaderFunc4<L, A0, A1, A2, A3>(func)); }
+
+ template<typename L, typename A0, typename A1, typename A2, typename A3, typename A4>
+ void add(const std::string &k, void (L::*func)(A0, A1, A2, A3, A4))
+ { add(k, new LoaderFunc5<L, A0, A1, A2, A3, A4>(func)); }
+ /**
+ Adds a keyword that is loaded into a variable of the loaded object.
+ */
template<typename L, typename T0>
void add(const std::string &k, T0 L::*p0)
- { actions.insert(typename ActionMap::value_type(k, new LoadValue1<L, T0>(p0))); }
+ { add(k, new LoadValue1<L, T0>(p0)); }
template<typename L, typename T0, typename T1>
void add(const std::string &k, T0 L::*p0, T1 L::*p1)
- { actions.insert(typename ActionMap::value_type(k, new LoadValue2<L, T0, T1>(p0, p1))); }
+ { add(k, new LoadValue2<L, T0, T1>(p0, p1)); }
+ /**
+ Adds a keyword that is recognized but ignored.
+ */
void add(const std::string &k)
- { actions.insert(ActionMap::value_type(k, 0)); }
+ { add(k, 0); }
/**
- Loads a sub-object from the statement being currently processed. The Loader
- class of the sub-object is automatically used.
+ Loads a sub-object from the statement being processed. The Loader class of
+ the sub-object is automatically used.
*/
template<typename S>
void load_sub(S &s)
- { load_sub<S, typename S::Loader>(s); }
+ {
+ typename S::Loader ldr(s);
+ load_sub_with(ldr);
+ }
/**
- Loads a sub-object with a custom Loader class.
+ Loads a sub-object from the statement being processed with an extra parameter
+ for the Loader. The Loader class of the sub-object is automatically used.
*/
- template<typename S, typename L>
- void load_sub(S &s)
+ template<typename S, typename T>
+ void load_sub(S &s, T &p)
{
- if(!cur_st)
- throw InvalidState("load_sub called without current statement");
- L loader(s);
- loader.load(*cur_st);
+ typename S::Loader ldr(s, p);
+ load_sub_with(ldr);
}
/**
- Loads a sub-object with a custom Loader class that takes one argument in
- addition to to object to be loaded.
+ Processes the current statement's substatements with another Loader.
*/
- template<typename S, typename L, typename T>
- void load_sub(S &s, T &p)
+ void load_sub_with(Loader &);
+
+ /**
+ Returns the source of the statement being processed. This can be used to
+ implement relative paths in include-like statements. Note that the source
+ may not necessarily be a file.
+ */
+ const std::string &get_source() const
{
if(!cur_st)
- throw InvalidState("load_sub called without current statement");
- L loader(s, p);
- loader.load(*cur_st);
+ throw InvalidState("get_source called without current statement");
+ return cur_st->source;
}
+
+ virtual void finish() { }
private:
typedef std::map<std::string, LoaderAction *> ActionMap;
ActionMap actions;
const Statement *cur_st;
+ void add(const std::string &, LoaderAction *);
void load_statement(const Statement &st);
};
template<typename T>
void load(T &obj, const std::string &fn)
{
- std::ifstream in(fn.c_str());
- if(!in)
- throw Exception("Couldn't open "+fn);
+ IO::File in(fn);
+ IO::Buffered buf(in);
- Parser parser(in, fn);
+ Parser parser(buf, fn);
typename T::Loader loader(obj);
loader.load(parser);
}
+template<typename T, typename U>
+void load(T &obj, const std::string &fn, U &arg)
+{
+ IO::File in(fn);
+ IO::Buffered buf(in);
+
+ Parser parser(in, fn);
+ typename T::Loader loader(obj, arg);
+ loader.load(parser);
+}
+
} // namespace DataFile
} // namespace Msp
projects / libs / datafile.git / blobdiff