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- [/==============================================================================
- Copyright (C) 2001-2011 Joel de Guzman
- Copyright (C) 2001-2011 Hartmut Kaiser
- Distributed under the Boost Software License, Version 1.0. (See accompanying
- file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
- ===============================================================================/]
- [section:basics Generator Basics]
- [heading Lazy Argument]
- Some generators (e.g. primitives and non-terminals) may take in additional
- attributes. Such generators take the form:
- g(a1, a2,..., aN)
- where `g` is a generator. Each of the arguments (a1 ... aN) can either be an
- immediate value, or a function, `f`, with signature:
- T f(Unused, Context)
- where `T`, the function's return value, is compatible with the argument
- type expected and `Context` is the generator's __karma_context__ type (The
- first argument is __unused__ to make the `Context` the second argument. This
- is done for uniformity with __karma_actions__).
- [heading Character Encoding Namespace]
- Some generators need to know which character set a `char` or `wchar_t` is
- operating on. For example, the `alnum` generator works differently with
- ISO8859.1 and ASCII encodings. Where necessary, Spirit encodes (tags)
- the generator with the character set.
- We have a namespace for each character set Spirit will be supporting.
- That includes `ascii`, `iso8859_1`, `standard` and `standard_wide` (and
- in the future, `unicode`). In each of the character encoding namespaces,
- we place tagged versions of generators such as `alnum`, `space` etc.
- Example:
- using boost::spirit::ascii::space; // use the ASCII space generator
- Namespaces:
- * boost::spirit::ascii
- * boost::spirit::iso8859_1
- * boost::spirit::standard
- * boost::spirit::standard_wide
- For ease of use, the components in this namespaces are also brought into
- the karma sub-namespaces with the same names:
- * boost::spirit::karma::ascii
- * boost::spirit::karma::iso8859_1
- * boost::spirit::karma::standard
- * boost::spirit::karma::standard_wide
- [heading Examples]
- All sections in the reference present some real world examples. The
- examples use a common test harness to keep the example code as minimal
- and direct to the point as possible. The test harness is presented
- below.
- Some includes:
- [reference_karma_includes]
- The used output iterator:
- [reference_karma_output_iterator]
- Our test functions:
- This one tests the generators without attributes.
- [reference_karma_test]
- These test the generators with one or more user supplied attributes.
- [reference_karma_test_attr]
- [reference_karma_test_attr2]
- This tests the generators with one attribute and while using delimited output.
- [reference_karma_test_attr_delim]
- The examples of the binary generators use one or more of the following tests.
- [reference_karma_binary_test]
- [reference_karma_binary_test_attr]
- [heading Models]
- Predefined models include:
- * any literal string, e.g. "Hello, World",
- * a pointer/reference to a null-terminated array of characters
- * a `std::basic_string<Char>`
- The namespace `boost::spirit::traits` is open for users to provide their
- own specializations. The customization points implemented by __karma__ usable
- to customize the behavior of generators are described in the section
- __sec_customization_points__.
- [endsect]
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