Code Fragment Collection

This is general template for building error catching and handling mechanism.

try {
    ... your code here...
}
catch(std::exception &e) {
    // error handling
    std::cerr << e.what() << std::endl ;
}
catch(...) {  // unknown exception
    std::cerr << "unknown exception" << std::endl ;
}

Load file content

#include <apl/file.cxx>

{
  std::string content ;
  apl::AFile<> file ;
  file.load("file.dat",content) ;
}

Read directory

#include <apl/file.cxx>

using namespace apl ;

{
  ADir<> dir ;
  ADir<>::file_list_type files ;
  dir.open(dirname) ;
  dir.read(filemask,files) ;
  for ( ADir<>::file_list_type::iterator f = files.begin(), f_end = files.end() ; f != f_end ; ++f ) {
    cout << f->name << endl ;  // process the file
  }
}

Make directory including parents

#include <apl/file.cxx>

using namespace apl ;

{
    AFileSystem<> fs ;
    fs.mkdir(dirname,fs.mkdir_parents) ;
}

Example of using typemap

#include <apl/typemap.cxx>

class Key1{} ;
class Key2{} ;
class Key3{} ;

class Value1{} ;
class Value2{} ;
class Value3{} ;

{
  using namespace apl ;
  typedef typemap::insert<Key1,Value1>::X Map2 ;
  typedef typemap::insert<Key2,Value2,Map2>::X Map3 ;
  typedef typemap::insert<Key3,Value3,Map3>::X Map4 ;

  cout << typeid(typemap::find<Key2,Map4>::X::Value).name() << endl ;
}

HTTP Request

#include <apl/http.cxx>

{
  ASocket<> sock ;
  AHttpClient<ASocket<> > http(sock) ;

  http.get("http://www.example.com/") ;

  std::cout << http.response.body << std::endl ;
}

Strip directory name and suffix

name=`basename $file_path $suffix`

IFS default value

On production scripts for security reasons it is always good to set IFS variable to its default value. By default IFS is set to tab, new line, and space.

old_IFS=$IFS
IFS=
IFS=`echo -n -e "\t\n\x20"`

# ... your code here ...

IFS=$old_IFS