lsst::afw::table::SubSchema Class Reference

A proxy type for name lookups in a Schema. More...

#include <Schema.h>

Public Member Functions
template<typename T >
SchemaItem< T >	find (std::string const &name) const
	Find a nested SchemaItem by name. More...
SubSchema	operator[] (std::string const &name) const
	Return a nested proxy. More...
std::string const &	getPrefix () const
	Return the prefix that defines this SubSchema relative to its parent Schema. More...
std::set< std::string >	getNames (bool topOnly=false) const
	Return a set of nested names that start with the SubSchema's prefix. More...
template<typename T >
	operator Key< T > () const
	Implicit conversion to the appropriate Key type. More...
template<typename T >
	operator Field< T > () const
	Implicit conversion to the appropriate Key type. More...

Private Types
typedef detail::SchemaImpl	Impl

Private Member Functions
	SubSchema (boost::shared_ptr< Impl > impl, boost::shared_ptr< AliasMap > aliases, std::string const &name)

Private Attributes
boost::shared_ptr< Impl >	_impl
boost::shared_ptr< AliasMap >	_aliases
std::string	_name

Friends
class	Schema

Detailed Description

A proxy type for name lookups in a Schema.

Elements of schema names are assumed to be separated by periods ("a.b.c.d"); an incomplete lookup is one that does not resolve to a field. Not that even complete lookups can have nested names; a Point field, for instance, has "x" and "y" nested names.

This proxy object is implicitly convertible to both the appropriate Key type and the appropriate Field type, if the name is a complete one, and supports additional find() operations for nested names.

SubSchema is implemented as a proxy that essentially calls Schema::find after concatenating strings. It does not provide any performance advantage over using Schema::find directly. It is also lazy, so looking up a name prefix that does not exist within the schema is not considered an error until the proxy is used.

Some examples:

*  Schema schema(false);
*  Key<int> a_i = schema.addField<int>("a.i", "integer field");
*  Key< Point<double> > a_p = schema.addField< Point<double> >("a.p", "point field");
*  
*  assert(schema["a.i"] == a_i);
*  SubSchema a = schema["a"];
*  assert(a["i"] == a_i);
*  Field<int> f_a_i = schema["a.i"];
*  assert(f_a_i.getDoc() == "integer field");
*  assert(schema["a.i"] == "a.i");
*  assert(schema.find("a.p.x") == a_p.getX());
*  

Definition at line 330 of file Schema.h.

Member Typedef Documentation

typedef detail::SchemaImpl lsst::afw::table::SubSchema::Impl

private

Definition at line 331 of file Schema.h.

Constructor & Destructor Documentation

lsst::afw::table::SubSchema::SubSchema ( boost::shared_ptr< Impl >  impl, boost::shared_ptr< AliasMap >  aliases, std::string const &  name  )

private

Member Function Documentation

template<typename T >

SchemaItem<T> lsst::afw::table::SubSchema::find

(

std::string const &

name

)

const

Find a nested SchemaItem by name.

std::set<std::string> lsst::afw::table::SubSchema::getNames

(

bool

topOnly = false

)

const

Return a set of nested names that start with the SubSchema's prefix.

Returns an instance of Python's builtin set in Python.

See Also

Schema::getNames

std::string const& lsst::afw::table::SubSchema::getPrefix ( ) const

inline

Return the prefix that defines this SubSchema relative to its parent Schema.

Definition at line 342 of file Schema.h.

{ return _name; }

template<typename T >

lsst::afw::table::SubSchema::operator Field< T > ( ) const

inline

Implicit conversion to the appropriate Key type.

Implicit conversion operators cannot be translated to Python. Instead, the SWIG wrappers provide an equivalent asField() method.

Definition at line 368 of file Schema.h.

{ return _impl->find<T>(_aliases->apply(_name)).field; }

template<typename T >

lsst::afw::table::SubSchema::operator Key< T > ( ) const

inline

Implicit conversion to the appropriate Key type.

Implicit conversion operators cannot be translated to Python. Instead, the SWIG wrappers provide an equivalent asKey() method.

Definition at line 359 of file Schema.h.

{ return _impl->find<T>(_aliases->apply(_name)).key; }

SubSchema lsst::afw::table::SubSchema::operator[]

(

std::string const &

name

)

const

Return a nested proxy.

Friends And Related Function Documentation

friend class Schema

friend

Definition at line 372 of file Schema.h.

Member Data Documentation

boost::shared_ptr< AliasMap > lsst::afw::table::SubSchema::_aliases

private

Definition at line 377 of file Schema.h.

boost::shared_ptr< Impl > lsst::afw::table::SubSchema::_impl

private

Definition at line 376 of file Schema.h.

std::string lsst::afw::table::SubSchema::_name

private

Definition at line 378 of file Schema.h.

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

• /home/lsstsw/stack/Linux64/afw/11.0-2-g04d2804/include/lsst/afw/table/Schema.h