diff --git a/examples/exMat.cpp b/examples/exMat.cpp
index 02609d0..45d95e2 100644
--- a/examples/exMat.cpp
+++ b/examples/exMat.cpp
@@ -1,5 +1,5 @@
 #include <iostream>
-#include <latan/Io.hpp>
+#include <latan/AsciiFile.hpp>
 #include <latan/Mat.hpp>
 #include <latan/Math.hpp>
 
diff --git a/examples/exRand.cpp b/examples/exRand.cpp
index 2229aaa..c50bfec 100644
--- a/examples/exRand.cpp
+++ b/examples/exRand.cpp
@@ -1,5 +1,5 @@
 #include <iostream>
-#include <latan/Io.hpp>
+#include <latan/AsciiFile.hpp>
 #include <latan/RandGen.hpp>
 
 using namespace std;
@@ -11,7 +11,7 @@ const string stateFileName = "exRand.seed";
 
 int main(void)
 {
-    RandGen::State state;
+    RandGenState state;
     RandGen gen[2];
     AsciiFile stateFile(stateFileName, File::Mode::write|File::Mode::read);
     
@@ -31,7 +31,7 @@ int main(void)
     }
     cout << "-- setting up another generator from '" << stateFileName << "'..."
          << endl;
-    gen[1].setState(stateFile.read<RandGen::State>("exRand"));
+    gen[1].setState(stateFile.read<RandGenState>("exRand"));
     cout << "-- generating a " << seqLength << " steps random sequence..."
          << endl;
     for (int i = 0; i < seqLength; ++i)
diff --git a/latan/AsciiFile.cpp b/latan/AsciiFile.cpp
new file mode 100644
index 0000000..61a965e
--- /dev/null
+++ b/latan/AsciiFile.cpp
@@ -0,0 +1,193 @@
+/*
+ * AsciiFile.cpp, part of LatAnalyze 3
+ *
+ * Copyright (C) 2013 - 2014 Antonin Portelli
+ *
+ * LatAnalyze 3 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 3 of the License, or
+ * (at your option) any later version.
+ *
+ * LatAnalyze 3 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 LatAnalyze 3.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <latan/AsciiFile.hpp>
+#include <latan/includes.hpp>
+
+using namespace std;
+using namespace Latan;
+
+/******************************************************************************
+ *                        AsciiFile implementation                            *
+ ******************************************************************************/
+// AsciiParserState constructor ////////////////////////////////////////////////
+AsciiFile::AsciiParserState::AsciiParserState(istream *stream, string *name,
+                                              IoDataTable *data)
+: ParserState<IoDataTable>(stream, name, data)
+{
+    initScanner();
+}
+
+// AsciiParserState destructor /////////////////////////////////////////////////
+AsciiFile::AsciiParserState::~AsciiParserState(void)
+{
+    destroyScanner();
+}
+
+// constructor /////////////////////////////////////////////////////////////////
+AsciiFile::AsciiFile(void)
+: File(), fileStream_()
+, isParsed_(false)
+, state_(nullptr)
+{}
+
+AsciiFile::AsciiFile(const string &name, const unsigned int mode)
+{
+    open(name, mode);
+}
+
+// destructor //////////////////////////////////////////////////////////////////
+AsciiFile::~AsciiFile(void)
+{
+    close();
+}
+
+// access //////////////////////////////////////////////////////////////////////
+void AsciiFile::save(const DMat &m, const std::string &name)
+{
+    checkWritability();
+    isParsed_ = false;
+    fileStream_ << "#L latan_begin mat " << name << endl;
+    fileStream_ << m.cols() << endl;
+    fileStream_ << scientific << m << endl;
+    fileStream_ << "#L latan_end mat " << endl;
+}
+
+void AsciiFile::save(const DMatSample &s, const std::string &name)
+{
+    checkWritability();
+    isParsed_ = false;
+    fileStream_ << "#L latan_begin rs_sample " << name << endl;
+    fileStream_ << s.size() << endl;
+    save(s[central], name + "_C");
+    for (int i = 0; i < static_cast<int>(s.size()); ++i)
+    {
+        save(s[i], name + "_S_" + strFrom(i));
+    }
+    fileStream_ << "#L latan_end rs_sample " << endl;
+}
+
+void AsciiFile::save(const RandGenState &state, const std::string &name)
+{
+    checkWritability();
+    isParsed_ = false;
+    fileStream_ << "#L latan_begin rg_state " << name << endl;
+    fileStream_ << state << endl;
+    fileStream_ << "#L latan_end rg_state " << endl;
+}
+
+// tests ///////////////////////////////////////////////////////////////////////
+bool AsciiFile::isOpen() const
+{
+    return fileStream_.is_open();
+}
+
+// IO //////////////////////////////////////////////////////////////////////////
+void AsciiFile::close(void)
+{
+    state_.reset();
+    if (isOpen())
+    {
+        fileStream_.close();
+    }
+    name_     = "";
+    mode_     = Mode::null;
+    isParsed_ = false;
+    deleteData();
+}
+
+void AsciiFile::open(const string &name, const unsigned int mode)
+{
+    if (isOpen())
+    {
+        LATAN_ERROR(Io, "file already opened with name '" + name_ + "'");
+    }
+    else
+    {
+        ios_base::openmode stdMode = static_cast<ios_base::openmode>(0);
+        
+        if (mode & Mode::write)
+        {
+            stdMode |= ios::out|ios::trunc;
+        }
+        if (mode & Mode::read)
+        {
+            stdMode |= ios::in;
+        }
+        if (mode & Mode::append)
+        {
+            stdMode |= ios::out|ios::app;
+        }
+        name_     = name;
+        mode_     = mode;
+        isParsed_ = false;
+        fileStream_.open(name_.c_str(), stdMode);
+        if (mode_ & Mode::read)
+        {
+            state_.reset(new AsciiParserState(&fileStream_, &name_, &data_));
+        }
+        else
+        {
+            state_.reset();
+        }
+    }
+}
+
+std::string AsciiFile::load(const string &name)
+{
+    if ((mode_ & Mode::read)&&(isOpen()))
+    {
+        if (!isParsed_)
+        {
+            state_->isFirst = true;
+            parse();
+        }
+        if (name.empty())
+        {
+            return state_->first;
+        }
+        else
+        {
+            return name;
+        }
+    }
+    else
+    {
+        if (isOpen())
+        {
+            LATAN_ERROR(Io, "file '" + name_ + "' is not opened in read mode");
+        }
+        else
+        {
+            LATAN_ERROR(Io, "file not opened");
+        }
+    }
+}
+
+// parser //////////////////////////////////////////////////////////////////////
+
+//// Bison/Flex parser declaration
+int _Ascii_parse(AsciiFile::AsciiParserState *state);
+
+void AsciiFile::parse()
+{
+    fileStream_.seekg(0);
+    _Ascii_parse(state_.get());
+    isParsed_ = true;
+}
diff --git a/latan/AsciiFile.hpp b/latan/AsciiFile.hpp
new file mode 100644
index 0000000..6bb8559
--- /dev/null
+++ b/latan/AsciiFile.hpp
@@ -0,0 +1,87 @@
+/*
+ * AsciiFile.hpp, part of LatAnalyze 3
+ *
+ * Copyright (C) 2013 - 2014 Antonin Portelli
+ *
+ * LatAnalyze 3 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 3 of the License, or
+ * (at your option) any later version.
+ *
+ * LatAnalyze 3 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 LatAnalyze 3.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef Latan_AsciiFile_hpp_
+#define Latan_AsciiFile_hpp_
+
+#include <latan/Global.hpp>
+#include <latan/File.hpp>
+#include <latan/Mat.hpp>
+#include <latan/RandGen.hpp>
+#include <latan/Sample.hpp>
+
+BEGIN_NAMESPACE
+
+/******************************************************************************
+ *                          ASCII datafile class                              *
+ ******************************************************************************/
+class AsciiFile: public File
+{
+public:
+    class AsciiParserState: public ParserState<IoDataTable>
+    {
+    public:
+        // constructor
+        explicit AsciiParserState(std::istream *stream, std::string *name,
+                                  IoDataTable *data);
+        // destructor
+        virtual ~AsciiParserState(void);
+        // first element reference
+        bool        isFirst;
+        std::string first;
+        // parsing buffers
+        RandGenState       stateBuf;
+        DMatSample         dMatSampleBuf;
+        std::queue<DMat>   dMatQueue;
+        std::queue<double> doubleQueue;
+        std::queue<int>    intQueue;
+    private:
+        // allocation/deallocation functions defined in IoAsciiLexer.lpp
+        virtual void initScanner(void);
+        virtual void destroyScanner(void);
+    };
+public:
+    // constructors
+    AsciiFile(void);
+    AsciiFile(const std::string &name, const unsigned int mode);
+    // destructor
+    virtual ~AsciiFile(void);
+    // access
+    virtual void save(const DMat &m, const std::string &name);
+    virtual void save(const DMatSample &s, const std::string &name);
+    virtual void save(const RandGenState &state, const std::string &name);
+    // tests
+    virtual bool isOpen(void) const;
+    // IO
+    virtual void close(void);
+    virtual void open(const std::string &name, const unsigned int mode);
+private:
+    // IO
+    virtual std::string load(const std::string &name = "");
+    // parser
+    void parse(void);
+private:
+    std::fstream                      fileStream_;
+    bool                              isParsed_;
+    std::unique_ptr<AsciiParserState> state_;
+};
+
+END_NAMESPACE
+
+#endif // Latan_AsciiFile_hpp_
diff --git a/latan/AsciiLexer.lpp b/latan/AsciiLexer.lpp
new file mode 100644
index 0000000..8e91f24
--- /dev/null
+++ b/latan/AsciiLexer.lpp
@@ -0,0 +1,95 @@
+/*
+ * IoAsciiLexer.lpp, part of LatAnalyze 3
+ *
+ * Copyright (C) 2013 - 2014 Antonin Portelli
+ *
+ * LatAnalyze 3 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 3 of the License, or
+ * (at your option) any later version.
+ *
+ * LatAnalyze 3 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 LatAnalyze 3.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+%option reentrant
+%option prefix="_Ascii_"
+%option bison-bridge
+%option bison-locations
+%option noyywrap
+%option yylineno
+
+%{
+    #include <iostream>
+	#include <latan/AsciiFile.hpp>
+	#include <latan/IOASCIIParser.hpp>
+    #pragma GCC diagnostic ignored "-Wsign-compare"
+    #pragma GCC diagnostic ignored "-Wunused-function"
+    #pragma GCC diagnostic ignored "-Wunused-parameter"
+
+    using namespace std;
+    using namespace Latan;
+    
+	#define YY_EXTRA_TYPE  AsciiFile::AsciiParserState*
+	#define YY_USER_ACTION \
+    yylloc->first_line   = yylloc->last_line = yylineno;\
+    yylloc->first_column = yylloc->last_column + 1;\
+    yylloc->last_column  = yylloc->first_column + yyleng - 1;
+
+	#define YY_INPUT(buf, result, max_size) \
+	{ \
+        (*yyextra->stream).read(buf,max_size);\
+        result = (*yyextra->stream).gcount();\
+	}
+    
+    #define YY_DEBUG 0
+    #if (YY_DEBUG == 1)
+    #define RETTOK(tok) cout << #tok << "(" << yytext << ")" << endl; return tok
+    #else
+    #define RETTOK(tok) return tok
+    #endif
+%}
+
+DIGIT   [0-9]
+ALPHA   [a-zA-Z_\-]
+SIGN    \+|-
+EXP     e|E
+INT     {SIGN}?{DIGIT}+
+FLOAT   {SIGN}?(({DIGIT}+\.{DIGIT}*)|({DIGIT}*\.{DIGIT}+))({EXP}{SIGN}?{INT}+)?
+LMARK   #L
+BLANK   [ \t]
+
+%x MARK TYPE
+
+%%
+
+{LMARK}            {BEGIN(MARK);}
+{INT}              {yylval->val_int    = strTo<int>(yytext);    RETTOK(INT);}
+{FLOAT}            {yylval->val_double = strTo<double>(yytext); RETTOK(FLOAT);}
+({ALPHA}|{DIGIT})+ {strcpy(yylval->val_str,yytext); RETTOK(ID);}
+<MARK>latan_begin  {BEGIN(TYPE); RETTOK(OPEN);}
+<MARK>latan_end    {BEGIN(TYPE); RETTOK(CLOSE);}
+<TYPE>mat          {BEGIN(INITIAL); RETTOK(MAT);}
+<TYPE>rs_sample    {BEGIN(INITIAL); RETTOK(SAMPLE);}
+<TYPE>rg_state     {BEGIN(INITIAL); RETTOK(RG_STATE);}
+<*>\n              {yylloc->last_column = 0;}
+<*>[ \t]
+<*>.               {yylval->val_char = yytext[0]; RETTOK(ERR);}
+
+%%
+
+void AsciiFile::AsciiParserState::initScanner()
+{
+	yylex_init(&scanner);
+	yyset_extra(this, scanner);
+}
+
+void AsciiFile::AsciiParserState::destroyScanner()
+{
+	yylex_destroy(scanner);
+}
diff --git a/latan/AsciiParser.ypp b/latan/AsciiParser.ypp
new file mode 100644
index 0000000..6665caa
--- /dev/null
+++ b/latan/AsciiParser.ypp
@@ -0,0 +1,188 @@
+/*
+ * IoAsciiParser.ypp, part of LatAnalyze 3
+ *
+ * Copyright (C) 2013 - 2014 Antonin Portelli
+ *
+ * LatAnalyze 3 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 3 of the License, or
+ * (at your option) any later version.
+ *
+ * LatAnalyze 3 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 LatAnalyze 3.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+%{
+    #include <iostream>
+    #include <memory>
+    #include <sstream>
+    #include <utility>
+    #include <cstring>
+    #include <latan/Global.hpp>
+	#include <latan/AsciiFile.hpp>
+    #include <latan/Mat.hpp>
+    #include <latan/RandGen.hpp>
+    #include <latan/Sample.hpp>
+
+    using namespace std;
+    using namespace Latan;
+    
+    #define TEST_FIRST(name) \
+    if (state->isFirst)\
+    {\
+        state->first   = (name);\
+        state->isFirst = false;\
+    }
+%}
+
+%pure-parser
+%name-prefix="_Ascii_"
+%locations
+%defines
+%error-verbose
+%parse-param { Latan::AsciiFile::AsciiParserState* state }
+%initial-action {yylloc.last_column = 0;}
+%lex-param { void* scanner }
+
+%union
+{
+	int    val_int;
+	double val_double;
+    char   val_char;
+    char   val_str[256];
+}
+
+%token <val_char>   ERR
+%token <val_double> FLOAT
+%token <val_int>    INT
+%token <val_str>    ID
+%token OPEN CLOSE MAT SAMPLE RG_STATE
+
+%type <val_str> mat sample rg_state
+
+%{
+	int _Ascii_lex(YYSTYPE* lvalp, YYLTYPE* llocp, void* scanner);
+
+	void _Ascii_error(YYLTYPE* locp, AsciiFile::AsciiParserState* state,
+                      const char* err)
+	{
+        stringstream buf;
+        
+        buf << *state->streamName << ":" << locp->first_line << ":"\
+            << locp->first_column << ": " << err;
+        LATAN_ERROR(Parsing, buf.str());
+	}
+
+	#define scanner state->scanner
+%}
+
+%%
+
+datas:
+      /* empty string */
+    | datas data
+	;
+
+data:
+      mat
+    {
+        TEST_FIRST($1);
+        (*state->data)[$1].reset(new DMat(state->dMatQueue.front()));
+        state->dMatQueue.pop();
+    }
+    | sample
+    {
+        TEST_FIRST($1);
+        (*state->data)[$1].reset(new DMatSample(state->dMatSampleBuf));
+    }
+    | rg_state
+    {
+        TEST_FIRST($1);
+        (*state->data)[$1].reset(new RandGenState(state->stateBuf));
+    }
+    ;
+
+mat:
+      OPEN MAT ID INT floats CLOSE MAT
+    {
+        const unsigned int nRow = state->doubleQueue.size()/$INT, nCol = $INT;
+        int i, j, r = 0;
+        
+        if (state->doubleQueue.size() != nRow*nCol)
+        {
+            LATAN_ERROR(Size, "matrix '" + *state->streamName + ":" + $ID +
+                        "' has a wrong size");
+        }
+        
+        state->dMatQueue.push(DMat(nRow, nCol));
+        while (!state->doubleQueue.empty())
+        {
+            j = r % nCol;
+            i = (r - j)/nCol;
+            state->dMatQueue.back()(i, j) = state->doubleQueue.front();
+            state->doubleQueue.pop();
+            r++;
+        }
+        strcpy($$, $ID);
+    }
+    ;
+
+sample:
+      OPEN SAMPLE ID INT mats CLOSE SAMPLE
+    {
+        const unsigned int nSample = $INT + 1;
+        
+        if (state->dMatQueue.size() != nSample)
+        {
+            LATAN_ERROR(Size, "sample '" + *state->streamName + ":" + $ID +
+                        "' has a wrong size");
+        }
+        state->dMatSampleBuf.resize(nSample);
+        state->dMatSampleBuf[central] = state->dMatQueue.front();
+        state->dMatQueue.pop();
+        for (int i = 0; i < $INT; ++i)
+        {
+            state->dMatSampleBuf[i] = state->dMatQueue.front();
+            state->dMatQueue.pop();
+        }
+        strcpy($$, $ID);
+    }
+
+rg_state:
+      OPEN RG_STATE ID ints CLOSE RG_STATE
+    {
+        if (state->intQueue.size() != RLXG_STATE_SIZE)
+        {
+            LATAN_ERROR(Size, "random generator state '" + *state->streamName
+                        + ":" + $ID + "' has a wrong size");
+        }
+        for (unsigned int i = 0; i < RLXG_STATE_SIZE; ++i)
+        {
+            state->stateBuf[i] = state->intQueue.front();
+            state->intQueue.pop();
+        }
+        strcpy($$, $ID);
+    }
+    ;
+
+mats:
+      mats mat
+    | mat
+    ;
+
+floats:
+      floats FLOAT {state->doubleQueue.push($FLOAT);}
+    | floats INT   {state->doubleQueue.push(static_cast<double>($INT));}
+    | FLOAT        {state->doubleQueue.push($FLOAT);}
+    | INT          {state->doubleQueue.push(static_cast<double>($INT));}
+    ;
+
+ints:
+      ints INT {state->intQueue.push($INT);}
+    | INT      {state->intQueue.push($INT);}
+    ;
diff --git a/latan/Dataset.hpp b/latan/Dataset.hpp
index fd3844f..336137c 100644
--- a/latan/Dataset.hpp
+++ b/latan/Dataset.hpp
@@ -21,7 +21,7 @@
 #define Latan_Dataset_hpp_
 
 #include <latan/Global.hpp>
-#include <latan/Io.hpp>
+#include <latan/File.hpp>
 #include <latan/Sample.hpp>
 #include <latan/RandGen.hpp>
 #include <fstream>
@@ -32,7 +32,7 @@ BEGIN_NAMESPACE
 /******************************************************************************
  *                              Dataset class                                 *
  ******************************************************************************/
-template <typename T, typename FileType>
+template <typename T>
 class Dataset: public StatArray<T>
 {
 private:
@@ -41,40 +41,43 @@ public:
     // constructors
     using Base::Base;
     Dataset(void);
+    template <typename FileType>
     Dataset(const std::string &listFileName, const std::string &dataName);
     // destructor
     virtual ~Dataset(void) = default;
     // IO
+    template <typename FileType>
     void load(const std::string &listFileName, const std::string &dataName);
     // resampling
     Sample<T> bootstrapMean(const unsigned int nSample, RandGen& generator);
 private:
     // mean from pointer vector for resampling
     void ptVectorMean(T &m, const std::vector<const T *> &v);
-private:
-    FileType file_;
 };
 
 /******************************************************************************
  *                      Dataset template implementation                       *
  ******************************************************************************/
 // constructor /////////////////////////////////////////////////////////////////
-template <typename T, typename FileType>
-Dataset<T, FileType>::Dataset(void)
+template <typename T>
+Dataset<T>::Dataset(void)
 {}
 
-template <typename T, typename FileType>
-Dataset<T, FileType>::Dataset(const std::string &listFileName,
-                              const std::string &dataName)
+template <typename T>
+template <typename FileType>
+Dataset<T>::Dataset(const std::string &listFileName,
+                    const std::string &dataName)
 {
-    load(listFileName, dataName);
+    load<FileType>(listFileName, dataName);
 }
 
 // IO //////////////////////////////////////////////////////////////////////////
-template <typename T, typename FileType>
-void Dataset<T, FileType>::load(const std::string &listFileName,
-                                const std::string &dataName)
+template <typename T>
+template <typename FileType>
+void Dataset<T>::load(const std::string &listFileName,
+                      const std::string &dataName)
 {
+    FileType file;
     std::ifstream listFile;
     char dataFileNameBuf[MAX_PATH_LENGTH];
     std::vector<std::string> dataFileName;
@@ -92,16 +95,16 @@ void Dataset<T, FileType>::load(const std::string &listFileName,
     this->resize(dataFileName.size());
     for (unsigned int i = 0; i < dataFileName.size(); ++i)
     {
-        file_.open(dataFileName[i], File::Mode::read);
-        (*this)[i] = file_.template read<T>(dataName);
-        file_.close();
+        file.open(dataFileName[i], File::Mode::read);
+        (*this)[i] = file.template read<T>(dataName);
+        file.close();
     }
 }
 
 // resampling //////////////////////////////////////////////////////////////////
-template <typename T, typename FileType>
-Sample<T> Dataset<T, FileType>::bootstrapMean(const unsigned int nSample,
-                                              RandGen& generator)
+template <typename T>
+Sample<T> Dataset<T>::bootstrapMean(const unsigned int nSample,
+                                    RandGen& generator)
 {
     unsigned int nData = this->size();
     std::vector<const T *> data(nData);
@@ -124,8 +127,8 @@ Sample<T> Dataset<T, FileType>::bootstrapMean(const unsigned int nSample,
     return s;
 }
 
-template <typename T, typename FileType>
-void Dataset<T, FileType>::ptVectorMean(T &m, const std::vector<const T *> &v)
+template <typename T>
+void Dataset<T>::ptVectorMean(T &m, const std::vector<const T *> &v)
 {
     if (v.size())
     {
diff --git a/latan/File.cpp b/latan/File.cpp
new file mode 100644
index 0000000..105edd3
--- /dev/null
+++ b/latan/File.cpp
@@ -0,0 +1,75 @@
+/*
+ * File.cpp, part of LatAnalyze 3
+ *
+ * Copyright (C) 2013 - 2014 Antonin Portelli
+ *
+ * LatAnalyze 3 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 3 of the License, or
+ * (at your option) any later version.
+ *
+ * LatAnalyze 3 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 LatAnalyze 3.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <latan/File.hpp>
+#include <latan/includes.hpp>
+
+using namespace std;
+using namespace Latan;
+
+/******************************************************************************
+ *                          File implementation                               *
+ ******************************************************************************/
+// constructors ////////////////////////////////////////////////////////////////
+File::File(void)
+: name_("")
+, mode_(Mode::null)
+, data_()
+{}
+
+File::File(const string &name, const unsigned int mode)
+: name_(name)
+, mode_(mode)
+, data_()
+{}
+
+// destructor //////////////////////////////////////////////////////////////////
+File::~File(void)
+{
+    deleteData();
+}
+
+// access //////////////////////////////////////////////////////////////////////
+const string & File::getName(void) const
+{
+    return name_;
+}
+
+unsigned int File::getMode(void) const
+{
+    return mode_;
+}
+
+// internal functions //////////////////////////////////////////////////////////
+void File::deleteData(void)
+{
+    for (auto &i : data_)
+    {
+        i.second.reset();
+    }
+    data_.clear();
+}
+
+void File::checkWritability(void)
+{
+    if (!((mode_ & Mode::write)||(mode_ & Mode::append))||!isOpen())
+    {
+        LATAN_ERROR(Io, "file '" + name_ + "' is not writable");
+    }
+}
diff --git a/latan/File.hpp b/latan/File.hpp
new file mode 100644
index 0000000..4975b4b
--- /dev/null
+++ b/latan/File.hpp
@@ -0,0 +1,161 @@
+/*
+ * File.hpp, part of LatAnalyze 3
+ *
+ * Copyright (C) 2013 - 2014 Antonin Portelli
+ *
+ * LatAnalyze 3 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 3 of the License, or
+ * (at your option) any later version.
+ *
+ * LatAnalyze 3 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 LatAnalyze 3.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef Latan_Io_hpp_
+#define	Latan_Io_hpp_
+
+#include <fstream>
+#include <memory>
+#include <queue>
+#include <sstream>
+#include <string>
+#include <unordered_map>
+#include <latan/Global.hpp>
+#include <latan/IoObject.hpp>
+#include <latan/ParserState.hpp>
+
+BEGIN_NAMESPACE
+
+// forward declaration of IO types
+class DMat;
+class DMatSample;
+class RandGen;
+class RandGenState;
+
+/******************************************************************************
+ *                          Abstract datafile class                           *
+ ******************************************************************************/
+typedef std::unordered_map<std::string, std::unique_ptr<IoObject>> IoDataTable;
+
+class File
+{
+public:
+    class Mode
+    {
+    public:
+        enum
+        {
+            null   = 0,
+            write  = 1 << 0,
+            read   = 1 << 1,
+            append = 1 << 2
+        };
+    };
+public:
+    // constructors
+    File(void);
+    File(const std::string &name, const unsigned int mode);
+    // destructor
+    virtual ~File(void);
+    // access
+    const std::string & getName(void) const;
+    unsigned int        getMode(void) const;
+    template <typename IoT>
+    const IoT &  read(const std::string &name = "");
+    virtual void save(const DMat &m, const std::string &name)             = 0;
+    virtual void save(const DMatSample &state, const std::string &name)   = 0;
+    virtual void save(const RandGenState &state, const std::string &name) = 0;
+    // tests
+    virtual bool isOpen(void) const = 0;
+    // IO
+    virtual void close(void)                                            = 0;
+    virtual void open(const std::string &name, const unsigned int mode) = 0;
+    // static IO functions
+    
+protected:
+    // access
+    void setName(const std::string &name);
+    void setMode(const unsigned int mode);
+    // data access
+    void deleteData(void);
+    // error checking
+    void checkWritability(void);
+private:
+    // data access
+    template <typename IoT>
+    const IoT& getData(const std::string &name = "") const;
+    // IO
+    virtual std::string load(const std::string &name = "") = 0;
+protected:
+    std::string  name_;
+    unsigned int mode_;
+    IoDataTable  data_;
+};
+
+// Template implementations
+template <typename IoT>
+const IoT& File::read(const std::string &name)
+{
+    std::string dataName;
+    
+    dataName = load(name);
+    
+    return getData<IoT>(dataName);
+}
+
+template <typename IoT>
+const IoT& File::getData(const std::string &name) const
+{
+    try
+    {
+        return dynamic_cast<const IoT &>(*(data_.at(name)));
+    }
+    catch(std::out_of_range)
+    {
+        LATAN_ERROR(Definition, "no data with name '" + name + "' in file "
+                    + name_);
+    }
+}
+
+/******************************************************************************
+ *                          Static IO functions                               *
+ ******************************************************************************/
+class Io
+{
+public:
+    template <typename IoT, typename FileType>
+    static IoT  load(const std::string &fileName, const std::string &name = "");
+    template <typename IoT, typename FileType>
+    static void save(const IoT &data, const std::string &fileName,
+                     const unsigned int mode = File::Mode::append,
+                     const std::string &name = "");
+};
+
+// template implementation /////////////////////////////////////////////////////
+template <typename IoT, typename FileType>
+IoT Io::load(const std::string &fileName, const std::string &name)
+{
+    FileType file(fileName, File::Mode::read);
+    
+    return file.template read<IoT>(name);
+}
+
+template <typename IoT, typename FileType>
+void Io::save(const IoT &data, const std::string &fileName,
+              const unsigned int mode, const std::string &name)
+{
+    FileType file(fileName, mode);
+    std::string realName = (name.empty()) ? fileName : name;
+    
+    file.template save(data, realName);
+}
+
+END_NAMESPACE
+
+#endif
diff --git a/latan/IoObject.hpp b/latan/IoObject.hpp
index d376fa0..2912023 100644
--- a/latan/IoObject.hpp
+++ b/latan/IoObject.hpp
@@ -24,7 +24,9 @@
 
 BEGIN_NAMESPACE
 
-// Abstract base for IO objects
+/******************************************************************************
+ *                        Abstract class for IO objects                       *
+ ******************************************************************************/
 class IoObject
 {
 public:
diff --git a/latan/Makefile.am b/latan/Makefile.am
index 2055b1f..373ada5 100644
--- a/latan/Makefile.am
+++ b/latan/Makefile.am
@@ -20,19 +20,20 @@ AM_YFLAGS = -d
 include eigen_files.mk
 nobase_dist_pkginclude_HEADERS = $(eigen_files)
 
-BUILT_SOURCES = IoAsciiParser.hpp MathParser.hpp
+BUILT_SOURCES = AsciiParser.hpp MathParser.hpp
 
 lib_LTLIBRARIES = liblatan.la
 	
 liblatan_la_SOURCES =   \
+    AsciiFile.cpp       \
+    AsciiParser.ypp     \
+    AsciiLexer.lpp      \
     CompiledFunction.cpp\
     Exceptions.cpp      \
     Function.cpp        \
     Global.cpp          \
     includes.hpp        \
-    Io.cpp              \
-    IoAsciiParser.ypp   \
-    IoAsciiLexer.lpp    \
+    File.cpp            \
     Mat.cpp             \
     Math.cpp            \
     MathInterpreter.cpp \
@@ -45,11 +46,12 @@ liblatan_la_SOURCES =   \
 	../config.h
 liblatan_ladir = $(pkgincludedir)
 liblatan_la_HEADERS =   \
+    AsciiFile.hpp       \
     CompiledFunction.hpp\
     Dataset.hpp         \
     Function.hpp        \
     Global.hpp          \
-    Io.hpp              \
+    File.hpp            \
     IoObject.hpp        \
     Mat.hpp             \
     Math.hpp            \
diff --git a/latan/RandGen.cpp b/latan/RandGen.cpp
index 5ba31a7..0517b08 100644
--- a/latan/RandGen.cpp
+++ b/latan/RandGen.cpp
@@ -28,18 +28,17 @@ using namespace std;
 using namespace Latan;
 
 /******************************************************************************
- *                        RandGen implementation                              *
+ *                      RandGenState implementation                           *
  ******************************************************************************/
-// State constructor ///////////////////////////////////////////////////////////
-RandGen::State::State(void)
-{}
-
-// State IO type ///////////////////////////////////////////////////////////////
-IoObject::IoType RandGen::State::getType(void) const
+// IO type ///////////////////////////////////////////////////////////////
+IoObject::IoType RandGenState::getType(void) const
 {
     return IoType::rgState;
 }
 
+/******************************************************************************
+ *                        RandGen implementation                              *
+ ******************************************************************************/
 // RanLxd implementation ///////////////////////////////////////////////////////
 RandGen::RanLxd::RanLxd(void)
 : init(0)
@@ -640,22 +639,22 @@ RandGen::RandGen(const int seed)
     generator_.rlxd_init(RLXD_LEVEL, seed);
 }
 
-RandGen::RandGen(const State &state)
+RandGen::RandGen(const RandGenState &state)
 {
     setState(state);
 }
 
 // state management ////////////////////////////////////////////////////////////
-RandGen::State RandGen::getState(void) const
+RandGenState RandGen::getState(void) const
 {
-    State state;
+    RandGenState state;
     
     generator_.rlxd_get(state.data());
     
     return state;
 }
 
-void RandGen::setState(const State &state)
+void RandGen::setState(const RandGenState &state)
 {
     generator_.rlxd_reset(state.data());
 }
diff --git a/latan/RandGen.hpp b/latan/RandGen.hpp
index 84cef25..c144fbc 100644
--- a/latan/RandGen.hpp
+++ b/latan/RandGen.hpp
@@ -27,25 +27,24 @@
 
 BEGIN_NAMESPACE
 
+class RandGenState: public Eigen::Array<int, RLXG_STATE_SIZE, 1>,
+                    public IoObject
+{
+private:
+    typedef Eigen::Array<int, RLXG_STATE_SIZE, 1> Base;
+public:
+    // destructor
+    virtual ~RandGenState(void) = default;
+    // IO type
+    IoType getType(void) const;
+};
+
 /******************************************************************************
  *                          Random generator class                            *
  ******************************************************************************/
 
 class RandGen
 {
-public:
-    class State: public Eigen::Array<int, RLXG_STATE_SIZE, 1>, public IoObject
-    {
-    private:
-        typedef Eigen::Array<int, RLXG_STATE_SIZE, 1> Base;
-    public:
-        // constructor
-        State(void);
-        // destructor
-        virtual ~State(void) = default;
-        // IO type
-        IoType getType(void) const;
-    };
 private:
     // Martin Luescher's ranlxd generator interface
     class RanLxd
@@ -85,12 +84,12 @@ public:
     // constructors
     RandGen(void);
     RandGen(const int seed);
-    RandGen(const State &state);
+    RandGen(const RandGenState &state);
     // destructor
     virtual ~RandGen(void) = default;
     // state management
-    State getState(void) const;
-    void  setState(const State &state);
+    RandGenState getState(void) const;
+    void         setState(const RandGenState &state);
     // generators
     double uniform(const double a = 0.0, const double b = 1.0);
     double discreteUniform(const unsigned int n);
diff --git a/utils/resample.cpp b/utils/resample.cpp
index f477a56..b8eb838 100644
--- a/utils/resample.cpp
+++ b/utils/resample.cpp
@@ -1,8 +1,8 @@
 #include <iostream>
 #include <libgen.h>
 #include <unistd.h>
+#include <latan/AsciiFile.hpp>
 #include <latan/Dataset.hpp>
-#include <latan/Io.hpp>
 
 #ifndef DEF_NSAMPLE
 #define DEF_NSAMPLE 100u
@@ -60,25 +60,25 @@ int main(int argc, char *argv[])
         usage(cmdName);
     }
     
-    Dataset<DMat, AsciiFile> dataset;
+    Dataset<DMat> dataset;
     DMatSample s;
     RandGen g;
     
     if (!stateFileName.empty())
     {
         AsciiFile f(stateFileName, File::Mode::read);
-        g.setState(f.read<RandGen::State>());
+        g.setState(f.read<RandGenState>());
     }
     cout << "-- loading data from manifest '" << manFileName << "'..." << endl;
-    dataset.load(manFileName, name);
+    dataset.load<AsciiFile>(manFileName, name);
     s = dataset.bootstrapMean(nSample, g);
     cout << scientific;
     cout << "central value:\n"      << s[central]               << endl;
     cout << "standard deviation:\n" << s.variance().cwiseSqrt() << endl;
     if (!outFileName.empty())
     {
-        AsciiFile f(outFileName, File::Mode::write);
-        f.save(s, manFileName + "_" + name);
+        Io::save<DMatSample, AsciiFile>(s, outFileName, File::Mode::write,
+                                        manFileName + "_" + name);
     }
     
     return EXIT_SUCCESS;
diff --git a/utils/sample_read.cpp b/utils/sample_read.cpp
index 6e6fae0..125a1f4 100644
--- a/utils/sample_read.cpp
+++ b/utils/sample_read.cpp
@@ -1,5 +1,5 @@
 #include <iostream>
-#include <latan/Io.hpp>
+#include <latan/AsciiFile.hpp>
 
 using namespace std;
 using namespace Latan;
@@ -13,10 +13,9 @@ int main(int argc, char *argv[])
     }
     
     string fileName = argv[1];
-    AsciiFile f(fileName, File::Mode::read);
     
     cout << "-- loading sample from '" << fileName << "'..." << endl;
-    const DMatSample &s = f.read<DMatSample>();
+    const DMatSample &s = Io::load<DMatSample, AsciiFile>(fileName);
     cout << scientific;
     cout << "central value:\n"      << s[central]               << endl;
     cout << "standard deviation:\n" << s.variance().cwiseSqrt() << endl;