libs/spirit/doc/qi/quick_reference.qbk
[/==============================================================================
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)
===============================================================================/]
This quick reference section is provided for convenience. You can use
this section as a sort of a "cheat-sheet" on the most commonly used Qi
components. It is not intended to be complete, but should give you an
easy way to recall a particular component without having to dig up on
pages and pages of reference documentation.
[section Common Notation]
[variablelist Notation
[[`P`] [Parser type]]
[[`p, a, b, c`] [Parser objects]]
[[`A, B, C`] [Attribute types of parsers `a`, `b` and `c`]]
[[`I`] [The iterator type used for parsing]]
[[`Unused`] [An `unused_type`]]
[[`Context`] [The enclosing rule's `Context` type]]
[[`attrib`] [An attribute value]]
[[`Attrib`] [An attribute type]]
[[`b`] [A boolean expression]]
[[`fp`] [A (lazy parser) function with signature `P(Unused, Context)`]]
[[`fa`] [A (semantic action) function with signature `void(Attrib, Context, bool&)`.
The third parameter is a boolean flag that can be set to false to
force the parse to fail. Both `Context` and the boolean flag are
optional.]]
[[`first`] [An iterator pointing to the start of input]]
[[`last`] [An iterator pointing to the end of input]]
[[`Ch`] [Character-class specific character type (See __char_class_types__)]]
[[`ch`] [Character-class specific character (See __char_class_types__)]]
[[`ch2`] [Character-class specific character (See __char_class_types__)]]
[[`charset`] [Character-set specifier string (example: "a-z0-9")]]
[[`str`] [Character-class specific string (See __char_class_types__)]]
[[`Str`] [Attribute of `str`: `std::basic_string<T>` where `T` is the underlying character type of `str`]]
[[`tuple<>`] [Used as a placeholder for a fusion sequence]]
[[`vector<>`] [Used as a placeholder for an STL container]]
[[`variant<>`] [Used as a placeholder for a boost::variant]]
[[`optional<>`] [Used as a placeholder for a boost::optional]]
]
[endsect]
[section:qi_parsers Qi Parsers]
[section:char Character Parsers]
[table
[[Expression] [Attribute] [Description]]
[[[qi_char `ch`]] [`Unused`] [Matches `ch`]]
[[[qi_char `lit(ch)`]] [`Unused`] [Matches `ch`]]
[[[qi_char `char_`]] [`Ch`] [Matches any character]]
[[[qi_char `char_(ch)`]] [`Ch`] [Matches `ch`]]
[[[qi_char `char_("c")`]] [`Ch`] [Matches a single char string literal, `c`]]
[[[qi_char `char_(ch, ch2)`]][`Ch`] [Matches a range of chars from `ch` to `ch2` (inclusive)]]
[[[qi_char `char_(charset)`]][`Ch`] [Matches a character set `charset`]]
[[[qi_char_class `alnum`]] [`Ch`] [Matches a character based on the equivalent of
`std::isalnum` in the current character set]]
[[[qi_char_class `alpha`]] [`Ch`] [Matches a character based on the equivalent of
`std::isalpha` in the current character set]]
[[[qi_char_class `blank`]] [`Ch`] [Matches a character based on the equivalent of
`std::isblank` in the current character set]]
[[[qi_char_class `cntrl`]] [`Ch`] [Matches a character based on the equivalent of
`std::iscntrl` in the current character set]]
[[[qi_char_class `digit`]] [`Ch`] [Matches a character based on the equivalent of
`std::isdigit` in the current character set]]
[[[qi_char_class `graph`]] [`Ch`] [Matches a character based on the equivalent of
`std::isgraph` in the current character set]]
[[[qi_char_class `print`]] [`Ch`] [Matches a character based on the equivalent of
`std::isprint` in the current character set]]
[[[qi_char_class `punct`]] [`Ch`] [Matches a character based on the equivalent of
`std::ispunct` in the current character set]]
[[[qi_char_class `space`]] [`Ch`] [Matches a character based on the equivalent of
`std::isspace` in the current character set]]
[[[qi_char_class `xdigit`]] [`Ch`] [Matches a character based on the equivalent of
`std::isxdigit` in the current character set]]
[[[qi_char_class `lower`]] [`Ch`] [Matches a character based on the equivalent of
`std::islower` in the current character set]]
[[[qi_char_class `upper`]] [`Ch`] [Matches a character based on the equivalent of
`std::isupper` in the current character set]]
]
[endsect]
[section:numeric Numeric Parsers]
[table
[[Expression] [Attribute] [Description]]
[[[qi_real_number `float_`]] [`float`] [Parse a floating point number into a `float`]]
[[[qi_real_number `float_(num)`]] [`float`] [Parse a floating point number into a `float`,
a number is matched only if it's `num`]]
[[[qi_real_number `double_`]] [`double`] [Parse a floating point number into a `double`]]
[[[qi_real_number `double_(num)`]] [`double`] [Parse a floating point number into a `double`,
a number is matched only if it's `num`]]
[[[qi_real_number `long_double`]] [`long double`] [Parse a floating point number into a `long double`]]
[[[qi_real_number `long_double(num)`]] [`long double`] [Parse a floating point number into a `long double`,
a number is matched only if it's `num`]]
[[[qi_unsigned_int `bin`]] [`unsigned`] [Parse a binary integer into an `unsigned`]]
[[[qi_unsigned_int `oct`]] [`unsigned`] [Parse an octal integer into an `unsigned`]]
[[[qi_unsigned_int `hex`]] [`unsigned`] [Parse a hexadecimal integer into an `unsigned`]]
[[[qi_unsigned_int `ushort_`]] [`unsigned short`] [Parse an unsigned short integer]]
[[[qi_unsigned_int `ushort_(num)`]] [`unsigned short`] [Parse an unsigned short integer,
a number is matched only if it's `num`]]
[[[qi_unsigned_int `ulong_`]] [`unsigned long`] [Parse an unsigned long integer]]
[[[qi_unsigned_int `ulong_(num)`]] [`unsigned long`] [Parse an unsigned long integer,
a number is matched only if it's `num`]]
[[[qi_unsigned_int `uint_`]] [`unsigned int`] [Parse an unsigned int]]
[[[qi_unsigned_int `uint_(num)`]] [`unsigned int`] [Parse an unsigned int,
a number is matched only if it's `num`]]
[[[qi_unsigned_int `ulong_long`]] [`unsigned long long`] [Parse an unsigned long long]]
[[[qi_unsigned_int `ulong_long(num)`]] [`unsigned long long`] [Parse an unsigned long long,
a number is matched only if it's `num`]]
[[[qi_signed_int `short_`]] [`short`] [Parse a short integer]]
[[[qi_signed_int `short_(num)`]] [`short`] [Parse a short integer,
a number is matched only if it's `num`]]
[[[qi_signed_int `long_`]] [`long`] [Parse a long integer]]
[[[qi_signed_int `long_(num)`]] [`long`] [Parse a long integer,
a number is matched only if it's `num`]]
[[[qi_signed_int `int_`]] [`int`] [Parse an int]]
[[[qi_signed_int `int_(num)`]] [`int`] [Parse an int,
a number is matched only if it's `num`]]
[[[qi_signed_int `long_long`]] [`long long`] [Parse a long long]]
[[[qi_signed_int `long_long(num)`]] [`long long`] [Parse a long long,
a number is matched only if it's `num`]]
]
[endsect]
[section:string String Parsers]
[table
[[Expression] [Attribute] [Description]]
[[[qi_lit_string `str`]] [`Unused`] [Matches `str`]]
[[[qi_lit_string `lit(str)`]] [`Unused`] [Matches `str`]]
[[[qi_lit_string `string(str)`]] [`Str`] [Matches `str`]]
[[__qi_symbols__] [N/A] [Declare a symbol table, `sym`. `Ch` is the
underlying char type of the symbol table keys.
`T` is the data type associated with each key.]]
[[
``
sym.add
(str1, val1)
(str2, val2)
/*...more...*/
;
``
]
[N/A] [Add symbols into a symbol table, `sym`.
val1 and val2 are optional data of type `T`,
the data type associated with each key.]]
[[`sym`] [`T`] [Matches entries in the symbol table, `sym`. If
successful, returns the data associated with
the key]]
]
[endsect]
[section:auxiliary Auxiliary Parsers]
[table
[[Expression] [Attribute] [Description]]
[[__qi_eol__] [`Unused`] [Matches the end of line (`\r` or `\n` or `\r\n`)]]
[[__qi_eoi__] [`Unused`] [Matches the end of input (first == last)]]
[[__qi_eps__] [`Unused`] [Match an empty string]]
[[__qi_eps__`(b)`] [`Unused`] [If `b` is true, match an empty string]]
[[__qi_lazy__`(fp)`] [Attribute of `P` where `P`
is the return type of `fp`] [Invoke `fp` at parse time, returning a parser
`p` which is then called to parse.]]
[[`fp`] [see `lazy(fp)` above] [Equivalent to `lazy(fp)`]]
[[__qi_attr__] [`Attrib`] [Doesn't consume/parse any input, but exposes the
argument `attrib` as its attribute.]]
]
[endsect]
[section:binary Binary Parsers]
[table
[[Expression] [Attribute] [Description]]
[[[qi_native_binary `byte_`]] [8 bits native endian] [Matches an 8 bit binary in native endian representation]]
[[[qi_native_binary `word`]] [16 bits native endian] [Matches a 16 bit binary in native endian representation]]
[[[qi_big_binary `big_word`]] [16 bits big endian] [Matches a 16 bit binary in big endian representation]]
[[[qi_little_binary `little_word`]] [16 bits little endian][Matches a 16 bit binary in little endian representation]]
[[[qi_native_binary `dword`]] [32 bits native endian] [Matches a 32 bit binary in native endian representation]]
[[[qi_big_binary `big_dword`]] [32 bits big endian] [Matches a 32 bit binary in big endian representation]]
[[[qi_little_binary `little_dword`]] [32 bits little endian][Matches a 32 bit binary in little endian representation]]
[[[qi_native_binary `qword`]] [64 bits native endian] [Matches a 64 bit binary in native endian representation]]
[[[qi_big_binary `big_qword`]] [64 bits big endian] [Matches a 64 bit binary in big endian representation]]
[[[qi_little_binary `little_qword`]] [64 bits little endian][Matches a 64 bit binary in little endian representation]]
]
[endsect]
[section:auto Auto Parsers]
See here for more information about [qi_auto Auto Parsers].
[table
[[Expression] [Attribute] [Description]]
[[[qi_auto `auto_`]] [`hold_any`] [Parse input using a parser
created from the supplied attribute type
using the __create_parser__ API function.]]
]
[endsect]
[section:directive Parser Directives]
[table
[[Expression] [Attribute] [Description]]
[[__qi_lexeme__`[a]`] [`A`] [Disable skip parsing for `a`, does pre-skipping]]
[[[qi_no_skip `no_skip[a]`]] [`A`] [Disable skip parsing for `a`, no pre-skipping]]
[[__qi_no_case__`[a]`] [`A`] [Inhibits case-sensitivity for `a`]]
[[__qi_omit__`[a]`] [`Unused`] [Ignores the attribute type of `a`]]
[[__qi_matches__`[a]`] [`bool`] [Return if the embedded parser `a` matched its input]]
[[__qi_as__`()[a]`] [`A`] [Force atomic assignment for arbitrary attribute types]]
[[__qi_as_string__`[a]`] [`A`] [Force atomic assignment for string attributes]]
[[__qi_as_wstring__`[a]`] [`A`] [Force atomic assignment for wide character string attributes]]
[[__qi_raw__`[a]`] [__boost_iterator_range__`<I>`] [Presents the transduction of `a` as an iterator range]]
[[__qi_expectd__`[a]`] [`A`] [Throw an exception if parsing `a` fails]]
[[[qi_repeat `repeat[a]`]] [`vector<A>`] [Repeat `a` zero or more times]]
[[[qi_repeat `repeat(N)[a]`]] [`vector<A>`] [Repeat `a` `N` times]]
[[[qi_repeat `repeat(N, M)[a]`]] [`vector<A>`] [Repeat `a` `N` to `M` times]]
[[[qi_repeat `repeat(N, inf)[a]`]] [`vector<A>`] [Repeat `a` `N` or more times]]
[[__qi_skip__`[a]`] [`A`] [Re-establish the skipper that got inhibited by lexeme or no_skip.]]
[[__qi_skip__`(p)[a]`] [`A`] [Use `p` as a skipper for parsing `a`]]
]
]
[endsect]
[section:operator Parser Operators]
[table
[[Expression] [Attribute] [Description]]
[[[link spirit.qi.reference.operator.not_predicate `!a`]]
[`Unused`] [Not predicate. If the predicate `a` matches,
fail. Otherwise, return a zero length match.]]
[[[link spirit.qi.reference.operator.and_predicate `&a`]]
[`Unused`] [And predicate. If the predicate `a` matches,
return a zero length match. Otherwise, fail.]]
[[[link spirit.qi.reference.operator.optional `-a`]]
[`optional<A>`] [Optional. Parse `a` zero or one time]]
[[[link spirit.qi.reference.operator.kleene `*a`]]
[`vector<A>`] [Kleene. Parse `a` zero or more times]]
[[[link spirit.qi.reference.operator.plus `+a`]]
[`vector<A>`] [Plus. Parse `a` one or more times]]
[[[link spirit.qi.reference.operator.alternative `a | b`]]
[`variant<A, B>`] [Alternative. Parse `a` or `b`]]
[[[link spirit.qi.reference.operator.sequence `a >> b`]]
[`tuple<A, B>`] [Sequence. Parse `a` followed by `b`]]
[[[link spirit.qi.reference.operator.expect `a > b`]]
[`tuple<A, B>`] [Expect. Parse `a` followed by `b`. `b` is
expected to match when `a` matches, otherwise,
an `expectation_failure` is thrown.]]
[[[link spirit.qi.reference.operator.difference `a - b`]]
[`A`] [Difference. Parse `a` but not `b`]]
[[[link spirit.qi.reference.operator.sequential_or `a || b`]]
[`tuple<`
`optional<A>,`
`optional<B> >`
] [Sequential Or. Parse `a` or `b` or `a` followed by `b`]]
[[[link spirit.qi.reference.operator.list `a % b`]]
[`vector<A>`] [List. Parse `a` delimited `b` one or more times]]
[[[link spirit.qi.reference.operator.permutation `a ^ b`]]
[`tuple<`
`optional<A>,`
`optional<B> >`
] [Permutation. Parse `a` or `b` or `a` followed by `b` or `b` followed by `a`.]]
]
[endsect]
[section:action Parser Semantic Actions]
[table
[[Expression] [Attribute] [Description]]
[[`p[fa]`] [Attribute of `p`] [Call semantic action, `fa` if p succeeds.]]
]
[endsect]
[endsect]
[section Compound Attribute Rules]
[heading Notation]
The notation we will use will be of the form:
a: A, b: B, ... --> composite-expression: composite-attribute
`a`, `b`, etc. are the operands. `A`, `B`, etc. are the operand's
attribute types. `composite-expression` is the expression involving the
operands and `composite-attribute` is the resulting attribute type of
the composite expression.
For instance:
a: A, b: B --> (a >> b): tuple<A, B>
reads as: given, `a` and `b` are parsers, and `A` is the type of the
attribute of `a`, and `B` is the type of the attribute of `b`, then the
type of the attribute of `a >> b` will be `tuple<A, B>`.
[important In the attribute tables, we will use `vector<A>` and
`tuple<A, B...>` as placeholders only. The notation of `vector<A>`
stands for ['any __stl__ container] holding elements of type `A` and the
notation `tuple<A, B...>` stands for ['any __fusion__ sequence] holding
`A`, `B`, ... etc. elements. Finally, `Unused` stands for
__unused_type__. ]
[heading Compound Parser Attribute Types]
[table
[[Expression] [Attribute]]
[[__qi_sequence__ (`a >> b`)]
[``a: A, b: B --> (a >> b): tuple<A, B>
a: A, b: Unused --> (a >> b): A
a: Unused, b: B --> (a >> b): B
a: Unused, b: Unused --> (a >> b): Unused
a: A, b: A --> (a >> b): vector<A>
a: vector<A>, b: A --> (a >> b): vector<A>
a: A, b: vector<A> --> (a >> b): vector<A>
a: vector<A>, b: vector<A> --> (a >> b): vector<A>``]]
[[__qi_expect__ (`a > b`)]
[``a: A, b: B --> (a > b): tuple<A, B>
a: A, b: Unused --> (a > b): A
a: Unused, b: B --> (a > b): B
a: Unused, b: Unused --> (a > b): Unused
a: A, b: A --> (a > b): vector<A>
a: vector<A>, b: A --> (a > b): vector<A>
a: A, b: vector<A> --> (a > b): vector<A>
a: vector<A>, b: vector<A> --> (a > b): vector<A>``]]
[[__qi_alternative__ (`a | b`)]
[``a: A, b: B --> (a | b): variant<A, B>
a: A, b: Unused --> (a | b): optional<A>
a: A, b: B, c: Unused --> (a | b | c): optional<variant<A, B> >
a: Unused, b: B --> (a | b): optional<B>
a: Unused, b: Unused --> (a | b): Unused
a: A, b: A --> (a | b): A``]]
[[__qi_difference__ (`a - b`)]
[``a: A, b: B --> (a - b): A
a: Unused, b: B --> (a - b): Unused``]]
[[__qi_kleene__ (`*a`)]
[``a: A --> *a: vector<A>
a: Unused --> *a: Unused``]]
[[__qi_plus__ (`+a`)]
[``a: A --> +a: vector<A>
a: Unused --> +a: Unused``]]
[[__qi_list__ (`a % b`)]
[``a: A, b: B --> (a % b): vector<A>
a: Unused, b: B --> (a % b): Unused``]]
[[[link spirit.qi.reference.directive.repeat `repeat(...,...)[a]`]]
[``a: A --> repeat(...,...)[a]: vector<A>
a: Unused --> repeat(...,...)[a]: Unused``]]
[[__qi_sequential_or__ (`a || b`)]
[``a: A, b: B --> (a || b): tuple<optional<A>, optional<B> >
a: A, b: Unused --> (a || b): optional<A>
a: Unused, b: B --> (a || b): optional<B>
a: Unused, b: Unused --> (a || b): Unused
a: A, b: A --> (a || b): vector<optional<A> >``]]
[[__qi_optional__ (`-a`)]
[``a: A --> -a: optional<A>
a: Unused --> -a: Unused``]]
[[`&a`] [`a: A --> &a: Unused`]]
[[`!b`] [`a: A --> !a: Unused`]]
[[__qi_permutation__ (`a ^ b`)]
[``a: A, b: B --> (a ^ b): tuple<optional<A>, optional<B> >
a: A, b: Unused --> (a ^ b): optional<A>
a: Unused, b: B --> (a ^ b): optional<B>
a: Unused, b: Unused --> (a ^ b): Unused``]]
]
[endsect]
[section:non_terminals Nonterminals]
[variablelist Notation
[[`RT`] [Synthesized attribute. The rule or grammar's return type.]]
[[`Arg1`, `Arg2`, `ArgN`] [Inherited attributes. Zero or more arguments.]]
[[`L1`, `L2`, `LN`] [Zero or more local variables.]]
[[`r, r2`] [Rules]]
[[`g`] [A grammar]]
[[`p`] [A parser expression]]
[[`my_grammar`] [A user defined grammar]]
]
[variablelist Terminology
[[Signature] [`RT(Arg1, Arg2 ... ,ArgN)`. The signature specifies
the synthesized (return value) and inherited (arguments)
attributes.]]
[[Locals] [`locals<L1, L2 ..., LN>`. The local variables.]]
[[Skipper] [The skip-parser type]]
]
[variablelist Template Arguments
[[`Iterator`] [The iterator type you will use for parsing.]]
[[`A1`, `A2`, `A3`] [Can be one of 1) Signature 2) Locals 3) Skipper.]]
]
[table
[[Expression] [Description]]
[[`rule<Iterator, A1, A2, A3> r(name);`] [Rule declaration. `Iterator` is required.
`A1, A2, A3` are optional and can be specified in any order.
`name` is an optional string that gives the rule
its name, useful for debugging and error handling.]]
[[`rule<Iterator, A1, A2, A3> r(r2);`] [Copy construct rule `r` from rule `r2`.]]
[[`r = r2;`] [Assign rule `r2` to `r`.]]
[[`r.alias()`] [return an alias of `r`. The alias is a parser that
holds a reference to `r`. Reference semantics.]]
[[`r.copy()`] [Get a copy of `r`.]]
[[`r.name(name)`] [Naming a rule]]
[[`r.name()`] [Getting the name of a rule]]
[[debug(r)] [Debug rule `r`]]
[[`r = p;`] [Rule definition]]
[[`r %= p;`] [Auto-rule definition. The attribute of `p` must be
compatible with the synthesized attribute of `r`. If `p`
is successful, its attribute is automatically propagated
to `r`'s synthesized attribute. Semantic actions, if present,
may not change the attribute's type.]]
[[
``
template <typename Iterator>
struct my_grammar : grammar<Iterator, A1, A2, A3>
{
my_grammar() : my_grammar::base_type(start, name)
{
// Rule definitions
start = /* ... */;
}
rule<Iterator, A1, A2, A3> start;
// more rule declarations...
};
``
] [Grammar definition. `name` is an optional string that gives the
grammar its name, useful for debugging and error handling.]]
[[`g.name(name)`] [Naming a grammar]]
[[`g.name()`] [Getting the name of a grammar]]
]
[endsect]
[section:semantic_actions Parser Semantic Actions]
Has the form:
p[f]
where `f` is a function with the signatures:
void f(Attrib const&);
void f(Attrib const&, Context&);
void f(Attrib const&, Context&, bool&);
You can use __boost_bind__ to bind member functions. For function
objects, the allowed signatures are:
void operator()(Attrib const&, unused_type, unused_type) const;
void operator()(Attrib const&, Context&, unused_type) const;
void operator()(Attrib const&, Context&, bool&) const;
The `unused_type` is used in the signatures above to signify 'don't
care'.
For more detailed information about semantic actions see:
[link spirit.qi.tutorials.semantic_actions here].
[endsect]
[section Phoenix]
__phoenix__ makes it easier to attach semantic actions. You just
inline your lambda expressions:
p[phoenix-lambda-expression]
Spirit.Qi provides some __phoenix__ placeholders to important
information from the `Attrib` and `Context` that are otherwise fiddly to extract.
[variablelist Spirit.Qi specific Phoenix placeholders
[[`_1, _2... , _N`] [Nth attribute of `p`]]
[[`_val`] [The enclosing rule's synthesized attribute.]]
[[`_r1, _r2... , _rN`] [The enclosing rule's Nth inherited attribute.]]
[[`_a, _b... , _j`] [The enclosing rule's local variables (`_a` refers to the first).]]
[[`_pass`] [Assign `false` to `_pass` to force a parser failure.]]
]
[important All placeholders mentioned above are defined in the namespace
`boost::spirit` and, for your convenience, are available in the
namespace `boost::spirit::qi` as well.]
For more detailed information about semantic actions see:
[link spirit.qi.tutorials.semantic_actions here].
[endsect]
