Boost C++ Libraries

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Nonterminals

See here for more information about Nonterminals.

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 generator expression
my_grammar: A user defined grammar

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.
Delimiter: The delimit-generator type

Template Arguments

Iterator: The iterator type you will use for parsing.
A1, A2, A3: Can be one of 1) Signature 2) Locals 3) Delimiter.

Expression	Description
`rule<OutputIterator, A1, A2, A3> r(name);`	Rule declaration. `OutputIterator` 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.
`rule<OutputIterator, A1, A2, A3> r(r2);`	Copy construct rule `r` from rule `r2`.
`r = r2;`	Assign rule `r2` to `r`. `boost::shared_ptr` semantics.
`r.alias()`	Return an alias of `r`. The alias is a generator that holds a reference to `r`. Reference semantics.
`r.copy()`	Get a copy of `r`.
`r.name(name)`	Set the name of a rule
`r.name()`	Get the name of a rule
debug(r)	Debug rule `r`
`r = g;`	Rule definition
`r %= g;`	Auto-rule definition. The attribute of `g` should be compatible with the synthesized attribute of `r`. When `g` is successful, its attribute is automatically propagated to `r`'s synthesized attribute.
template <typename OutputIterator> struct my_grammar : grammar<OutputIterator, A1, A2, A3> { my_grammar() : my_grammar::base_type(start, name) { // Rule definitions start = /* ... */; } rule<OutputIterator, A1, A2, A3> start; // more rule declarations... };	Grammar definition. `name` is an optional string that gives the grammar its name, useful for debugging.
my_grammar<OutputIterator> g	Instantiate a grammar
`g.name(name)`	Set the name of a grammar
`g.name()`	Get the name of a grammar