* means to deploy types that do not meet the [@http://en.cppreference.com/w/cpp/named_req/DefaultConstructible ['Default Constructibility]] requirement;
* four types of the conversion-failure ['detection]:
* as part of the same process flow -- basic and generic;
* as a branched process flow -- exception-based and function-based;
* the choice of immediate or delayed exception-throwing and non-throwing conversion-failure ['processing];
* flexibility of conversion-failure ['processing] via:
* an exception thrown;
* the fallback value returned;
* the fallback function called;
* support for standard algorithms.
['Boost.Convert] consists of two components:
* the `boost::convert()` interface;
* an extendible collection of pluggable converters.
The `boost::convert()` interface
* advertises, provides and ensures certain ['consistent behavior];
* unifies and provides ['one consistent interface] to various conversion facilities.
The collection of pluggable converters is independent of the `boost::convert()` API facade and is designed to be ['extendible] and extended over time. Currently the following converters are provided:
* `boost::lexical_cast`-based,
* `printf/scanf`-based,
* `strtol`-inspired,
* `std::stringstream`-based,
* `boost::spirit`-based.
The converters provide new and familiar functionality and demonstrate how existing and independent conversion facilities might be incorporated in to the ['Boost.Convert] framework. For example, the `std::stream`-based converter draws on the standard `std::streams` functionality and provides:
* string-to-type and type-to-string conversions;
* formatting support (`std::ios`-based precision, base, upper/lower-case, scientific, etc.);
