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Container Utilities
Description: container formatters and converters.Keywords: ecl container utilities
Tutorial Level: INTERMEDIATE
Formatters
Currently there is only limited support for formatters of the array and stencil classes classes:
- precision/width formatting for float arrays.
- hex formatting for byte arrays (signed char/char/unsigned char).
- default formatting for other types of arrays (provided they have the required Format for the element type).
- formatting extends to stencils operating on the array.
1 #include <ecl/array.hpp>
2
3 Array<unsigned char>::Formatter format;
4 Array<unsigned char> array;
5 array << 0x01, 0x02, 0x03, 0x04;
6 std::cout << format(array) << std::endl;
7 // OR
8 #include <ecl/array.hpp>
9 #include <ecl/format.hpp>
10
11 Format< Array<unsigned char> > format;
12 Array<unsigned char> array;
13 array << 0x01, 0x02, 0x03, 0x04;
14 std::cout << format(array) << std::endl;
See also ecl_formatters.
Byte Array Converters
These are often useful for interacting with io devices.
Some converters utilising the FromByteArray template class from ecl_converters have specialisations here for arrays and stencils respectively. These allow conversion to integers of any time from a corresponding, little endian filled array/stencil of chars.
1 typedef Array<char, 4> ByteArray;
2 ByteArray byte_array;
3
4 byte_array << 0x01, 0x02, 0x03;
5 ecl::Converter<int,ByteStencil> toInt;
6 std::cout << "Conversion: " << toInt(byte_array) << std::endl; // results in 197121
7 std::cout << "Conversion: " << toInt(byte_array.stencil(0,2)) << std::endl; // only first two bytes -> 513
8
and going the other way, we pass it the byte array for storage when converting (works on both arrays and stencils)...
1 Array<char,20> byte_array = Array<char,20>::Constant(0x00);
2 Stencil< Array<char, 20> > stencil = byte_array.stencil(2,4);
3 ecl::Converter< Stencil< Array<char, 20> >, ecl::int32 > fromInt;
4 fromInt(stencil, ecl::int32(197121));
5 std::cout << byte_array << std::endl; // 0x00, 0x00, 0x01, 0x02, 0x03, 0x00, 0x00, 0x00, ...
6 std::cout << stencil << std::endl; // 0x01, 0x02, 0x03, 0x00
7
