casa::AipsrcValue< T > Class Template Reference
[System]

#include <AipsrcValue.h>

Inheritance diagram for casa::AipsrcValue< T >:

[legend]Collaboration diagram for casa::AipsrcValue< T >:

[legend]List of all members.

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Detailed Description

template<class T>
class casa::AipsrcValue< T >

Class to read values from the Aipsrc general resource files.

Intended use:

Part of API

Review Status

Reviewed By:

mhaller

Date Reviewed:

1997/10/08

Test programs:

tAipsrcValue

Prerequisite

• Aipsrc

Etymology

A class for getting values from the Aipsrc files

Synopsis

The static AipsrcValue class can get typed values from the Aipsrc resource files.
The basic interaction with the class is with the static keyword match functions:

    Bool AipsrcValue<Type>::find(Type &result, const String &keyword)
    Bool AipsrcValue<Type>::find(Type &result, const String &keyword,
                                const Type &deflt)

comparable to the standard (String) Aipsrc find.
If the resource file contains a multi-valued keyword, use the AipsrcVector class instead.

The class is templated. For ease of use typedefs are provided for:

    AipsrcDouble, AipsrcInt, AipsrcBool, AipsrcString
    AipsrcVDouble, AipsrcVInt, AipsrcVBool, AipsrcVString

In addition to the above finds, special finds:

    Bool AipsrcValue<Type>::find(Type &result, const String &keyword,
                                const Unit &defun, const Unit &resun)
    Bool AipsrcValue<Type>::find(Type &result, const String &keyword,
                                const Unit &defun, const Unit &resun,
                                const Type &deflt)

are provided. These finds will read the keyword value as a Quantity. If no units are given, the defun are assumed. The result is converted to the resun, before the value is returned. E.g.

        Double x;
        find(x, "time.offset", "h", "d");

will return:

• 2.5/24 for a value specified as 2.5 in resource file
• 2.5/24 for 2:30:00
• 0.5/24 for 30min
• 0.5 for 0.5d

The class has registerRC, get, set functions as described in Aipsrc . Note that registration is on a per Type basis, and hence registration of the same keyword in different types (and possible sets) act on different values, but with the same result if no set has been done.

Specialisation exists for Bool, where True is any value string starting with one of 'yYtT123456789', and False in all other cases, and no finds with Units are provided. Strings are supposed to be handled by standard Aipsrc class for single values, and a specialisation exists for the AipsrcVector case.

Example

     String tzoff;              // result of keyword find
     if (!AipsrcValue<Double>::find(tzoff, "time.zone.offset")) {       // look for key
       tzoff = -5;
     };

A more convenient way of accomplishing the same result is:

       AipsrcDouble::find(tzoff, "time.zone.offset", -5);

or even:

       AipsrcDouble::find(tzoff, "time.zone.offset",
                         "h", "h", -5);

Here the final argument is the default to use if the keyword is not found at all.

Template Type Argument Requirements

• All types with a >> defined. Warning: Since interpretation of the keyword value string is done with the standard input right-shift operator, specialisations are necessary for non-standard cases like Bool. They are provided. String is supposed to be handled by standard Aipsrc.

Motivation

Programs need a way to interact with the AipsrcValue files.

Thrown Exceptions

• AipsError if the environment variables HOME and/or AIPSPATH not set.

To Do

Definition at line 157 of file AipsrcValue.h.

Public Member Functions
	AipsrcValue ()
	Default constructor Tip: A constructor (and destructor) have been provided to be able to generate a (routine-level) static register list.
	~AipsrcValue ()
	See note with constructor.
template<>
Bool	find (String &value, const String &keyword, const Unit &defun, const Unit &resun)
Static Public Member Functions
static void	save (uInt keyword)
	Save registered value to $HOME/.aipsrc.
static Bool	find (T &value, const String &keyword)
	The find() functions will, given a keyword, return the value of a matched keyword found in the files.
static Bool	find (T &value, const String &keyword, const T &deflt)
static Bool	find (T &value, const String &keyword, const Unit &defun, const Unit &resun)
	These find() functions will, given a keyword, read the value of a matched keyword as a Quantity.
static Bool	find (T &value, const String &keyword, const Unit &defun, const Unit &resun, const T &deflt)
static uInt	registerRC (const String &keyword, const T &deflt)
	Functions to register keywords for later use in get() and set().
static uInt	registerRC (const String &keyword, const Unit &defun, const Unit &resun, const T &deflt)
static const T &	get (uInt keyword)
	Gets are like find, but using registered integers rather than names.
static void	set (uInt keyword, const T &deflt)
	Sets allow registered values to be set.
Private Member Functions
AipsrcValue< T > &	operator= (const AipsrcValue< T > &other)
	Copy constructor (not implemented).
	AipsrcValue (const AipsrcValue< T > &other)
Private Attributes
Block< T >	tlst
	Register list.
Block< String >	ntlst
Static Private Attributes
static AipsrcValue	myp_p
	The global AipsrcValue object.

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Constructor & Destructor Documentation

template<class T>

casa::AipsrcValue< T >::AipsrcValue

(

)

Default constructor Tip: A constructor (and destructor) have been provided to be able to generate a (routine-level) static register list.

This had to be done since static data members are not yet implemented in the gcc compiler for templated classes. Once they are available the tlist and ntlst data can become static, constructor and desctructor and all references to the init() method can disappear.

template<class T>

casa::AipsrcValue< T >::~AipsrcValue

(

)

See note with constructor.

template<class T>

casa::AipsrcValue< T >::AipsrcValue

(

const AipsrcValue< T > &

other

)

[private]

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Member Function Documentation

template<class T>

static Bool casa::AipsrcValue< T >::find	(	T &	value,
		const String &	keyword
	)			[static]

The find() functions will, given a keyword, return the value of a matched keyword found in the files.

If no match found the function will be False, and the default returned if specified.

template<class T>

static Bool casa::AipsrcValue< T >::find	(	T &	value,
		const String &	keyword,
		const T &	deflt
	)			[static]

template<class T>

static Bool casa::AipsrcValue< T >::find	(	T &	value,
		const String &	keyword,
		const Unit &	defun,
		const Unit &	resun
	)			[static]

These find() functions will, given a keyword, read the value of a matched keyword as a Quantity.

If no unit has been given in the keyword value, the defun Unit will be assumed. The value returned will be converted to the resun Unit. If no match found, the default value is returned (see example above).

template<class T>

static Bool casa::AipsrcValue< T >::find	(	T &	value,
		const String &	keyword,
		const Unit &	defun,
		const Unit &	resun,
		const T &	deflt
	)			[static]

template<class T>

static uInt casa::AipsrcValue< T >::registerRC	(	const String &	keyword,
		const T &	deflt
	)			[static]

Functions to register keywords for later use in get() and set().

The returned value is the index for get() and set().

template<class T>

static uInt casa::AipsrcValue< T >::registerRC	(	const String &	keyword,
		const Unit &	defun,
		const Unit &	resun,
		const T &	deflt
	)			[static]

template<class T>

static const T& casa::AipsrcValue< T >::get

(

uInt

keyword

)

[static]

Gets are like find, but using registered integers rather than names.

The aipsrc file is read only once, and values can be set as well.

Reimplemented from casa::Aipsrc.

template<class T>

static void casa::AipsrcValue< T >::set	(	uInt	keyword,
		const T &	deflt
	)			[static]

Sets allow registered values to be set.

template<class T>

static void casa::AipsrcValue< T >::save

(

uInt

keyword

)

[static]

Save registered value to $HOME/.aipsrc.

Reimplemented from casa::Aipsrc.

template<class T>

AipsrcValue<T>& casa::AipsrcValue< T >::operator=

(

const AipsrcValue< T > &

other

)

[private]

Copy constructor (not implemented).

template<>

Bool casa::AipsrcValue< String >::find	(	String &	value,
		const String &	keyword,
		const Unit &	defun,
		const Unit &	resun
	)

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Member Data Documentation

template<class T>

AipsrcValue casa::AipsrcValue< T >::myp_p [static, private]

The global AipsrcValue object.

Definition at line 222 of file AipsrcValue.h.

template<class T>

Block<T> casa::AipsrcValue< T >::tlst [private]

Register list.

Definition at line 225 of file AipsrcValue.h.

template<class T>

Block<String> casa::AipsrcValue< T >::ntlst [private]

Definition at line 226 of file AipsrcValue.h.

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

• casa/implement/System/AipsrcValue.h

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