Parsnip::Evaluator Class Reference

Evaluator base class. More...

#include <parsnip_evaluate.h>

Inheritance diagram for Parsnip::Evaluator:

Public Types
using	StringType = std::string
using	CommandId = int

Public Member Functions
	Evaluator (Evaluator *original)
	Upgrade an evaluator.
int	evaluate (ArgvCursor *cursor, Parsnip::Data &result_dict)
	Evaluate a token in the command line, and recurse if there is more to go.
virtual bool	operator== (const Evaluator &) const
	Check if two evaluators are the same.
bool	operator!= (const Evaluator &other) const

Static Public Member Functions
static void	construct (EvaluatorRef &evaluator, const ArgvCursor &cursor, CommandId id, Parser *parent_parser)
	Construct token handler from the token in a parsing definition.

Protected Member Functions
void	setCommandId (CommandId id)
	Set the command ID in an evaluator.
virtual Evaluator *	getNextEvaluator (const StringType &token) const =0
	Determine if and how to evaluate additional command line tokens.
virtual Parsnip::Data	evaluateToken (class ArgvCursor *cursor) const =0
	Evaluate command line tokens.
virtual void	convertToOptionEvaluator ()=0
	Make any changes to the parse tree to convert it to an options evaluator.
virtual void	constructSchema (const DictionarySchema &schema, const Schema::OptionSchemas &option_schemas, const SchemaIntegratorCallback &integrator) const =0
	Construct a schema from an evaluator tree.

Static Protected Member Functions
static void	set_name (EvaluatorRef &target, const std::string &name)
	Assign a name by which to store values for value evaluators.

Protected Attributes
CommandId	command_id {NoCommand}
	If this completes a command, the command ID.
std::string	name
	If not empty, the name by which this value shall be accessed.

Friends
class	ValueEvaluator
class	KeywordEvaluator
class	RemainingValuesEvaluator
class	RemainderEvaluator
class	OptionEvaluator
class	OptionParser
class	Schema
class	SchemaSet

Detailed Description

Evaluator base class.

Constructor & Destructor Documentation

Evaluator()

Parsnip::Evaluator::Evaluator

(

Evaluator *

original

)

Upgrade an evaluator.

The original must be a TerminatorEvaluator; other type should never be upgraded. Herein we initialize the new evaluator with the relevant bits.

Member Function Documentation

construct()

void Parsnip::Evaluator::construct ( EvaluatorRef &  parser, const ArgvCursor &  cursor, CommandId  id, Parser *  parent_parser  )

static

Construct token handler from the token in a parsing definition.

Parameters

parser	The parser to update or construct with new definitions.
cursor	Points to the token defining what to construct.
id	The command ID to use for completed commands of this definition.
parent_parser	Passed through; see ValueEvaluator::construct.

constructSchema()

virtual void Parsnip::Evaluator::constructSchema ( const DictionarySchema &  schema, const Schema::OptionSchemas &  option_schemas, const SchemaIntegratorCallback &  integrator  ) const

protectedpure virtual

Construct a schema from an evaluator tree.

This function depth-first searches the evaluation tree, calling the integrator function at leaf nodes and other valid statement endpoints.

Parameters

schema	The schema, as constructed from the parse tree root.
option_schemas	Schemas for option parsers that may be needed.
integrator	An integrator that merges various statement patterns into a complete schema.

Exceptions

NoSuchKey	A necessary option schema was not found.
SchemaConflict	Statement definitions generate schema inconsistencies.

Implemented in Parsnip::ValueEvaluator, Parsnip::KeywordEvaluator, Parsnip::RemainingValuesEvaluator, and Parsnip::OptionEvaluator.

convertToOptionEvaluator()

virtual void Parsnip::Evaluator::convertToOptionEvaluator ( )

protectedpure virtual

Make any changes to the parse tree to convert it to an options evaluator.

Implemented in Parsnip::ValueEvaluator, Parsnip::KeywordEvaluator, and Parsnip::RemainderEvaluator.

evaluate()

int Parsnip::Evaluator::evaluate	(	ArgvCursor *	cursor,
		Parsnip::Data &	result_dict
	)

Evaluate a token in the command line, and recurse if there is more to go.

Parameters

cursor	Provides the command line tokens.
result_dict	Dictionary into which to put values.

Returns

ID code of command selected.

evaluateToken()

virtual Parsnip::Data Parsnip::Evaluator::evaluateToken ( class ArgvCursor *  cursor ) const

protectedpure virtual

Evaluate command line tokens.

Parameters

cursor

Provides tokens from the command line. Must be bumped forward as they are processed.

Returns

Parsnip data object containing evaluated token.

Implemented in Parsnip::StringEvaluator, Parsnip::RegExEvaluator, Parsnip::RawRemainderEvaluator, Parsnip::IntegerEvaluator, Parsnip::RealEvaluator, Parsnip::KeywordEvaluator, Parsnip::RemainingValuesEvaluator, and Parsnip::OptionEvaluator.

getNextEvaluator()

virtual Evaluator * Parsnip::Evaluator::getNextEvaluator ( const StringType &  token ) const

protectedpure virtual

Determine if and how to evaluate additional command line tokens.

Parameters

token

The current token being evaluated.

Returns

The evaluator for the next token, or nullptr if evaluation is complete.

Implemented in Parsnip::KeywordEvaluator, Parsnip::ValueEvaluator, and Parsnip::RemainderEvaluator.

operator==()

bool Parsnip::Evaluator::operator== ( const Evaluator &  other ) const

virtual

Check if two evaluators are the same.

Subclasses should override this to check their details.

Parameters

other

Another evaluator to which to compare.

Reimplemented in Parsnip::OptionEvaluator, Parsnip::ValueEvaluator, Parsnip::RegExEvaluator, Parsnip::IntegerEvaluator, Parsnip::RealEvaluator, Parsnip::KeywordEvaluator, and Parsnip::RemainderEvaluator.

set_name()

void Parsnip::Evaluator::set_name ( EvaluatorRef &  target, const std::string &  nam  )

staticprotected

Assign a name by which to store values for value evaluators.

There must be no prior name, or the same as the prior name.

Parameters

target	The evalutor whose name to set. If necessary, the target is instantiated.
nam	The name. If empty the assignment is ignored.

setCommandId()

void Parsnip::Evaluator::setCommandId ( CommandId  id )

protected

Set the command ID in an evaluator.

The ID must not be redefined/changed.

Parameters

id	The ID being set.

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The documentation for this class was generated from the following files:

• parsnip/parsnip_evaluate.h
• parsnip/parsnip_command.cpp
• parsnip/parsnip_evaluate.cpp