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String::Tagged::FormatUser(Contributed Perl DocumString::Tagged::Formatting(3)

       "String::Tagged::Formatting" - an API specification for simple
       formatted strings

       A primary use case of String::Tagged is to allow	storage	of a text
       string with associated formatting data. As there	are a growing number
       of subclasses on	CPAN that attempt to do	this, a	common specification
       is emerging to allow interoperability between them. This	will allow
       interchange between formats from	different sources, display or
       rendering, and so on.

       Primarily this specification consists of	the names and meanings of a
       set of tags that	a conforming string should supply, though it also
       suggests	a pair of methods useful for converting	between	different
       types of	object and the standard	formatting. Specific implementations
       may not be able to represent all	of the tags of course; this
       specification only gives	the suggested way to represent those
       formatting styles that the implementation actually understands.

   bold, under,	italic,	strike,	blink, monospace
       Tags with boolean values	indicating bold, underline, italic,
       strikethrough, blinking and monospaced font.

       Tag with	boolean	value indicating reverse video;	i.e. the effect	of
       swapping	foreground and background colours. This	effect is common on
       terminal-based string systems, but is unlikely to be found elsewhere.

   fg, bg
       Tags with Convert::Color	instances giving foreground and	background
       colours.	The use	of a "Convert::Color" instance allows specific
       implementations to be able to represent their own colour	space, while
       still supporting	an easy	conversion to the colour spaces	used by

       The following methods should be provided	on conforming implementations,
       to indicate their support of this specification and to allow easy
       conversion from and to it.

	 $fmt =	$st->as_formatting

       Called on an existing instance of the class, returns a "String::Tagged"
       instance	(or some subclass thereof) containing only the tags and	values
       defined by this specification. This method may simply return the
       original	instance if the	tags natively used by it already fit this
       specification, or it may	return a newly-constructed instance by
       converting its own tag formats.

       Use of the "clone" method with "only_tags" and possibly a
       "convert_tags" map should be able to implement this in most cases.

	 $st = String::Tagged::Subclass->new_from_formatting( $fmt )

       Called as a class method	on the target class type, returns a new
       instance	of that	class constructed to represent the formatting
       contained in the	$fmt instance, which should contain only the tags
       given in	this specification. If the class natively uses tags as per
       this specification, this	can be a trivial clone,	otherwise some
       conversion will need to be performed.

       Use of the "clone" method with "only_tags" and possibly a
       "convert_tags" map should be able to implement this in most cases.

       o   Net::Async::Matrix::Utils - Contains	a pair of functions to convert
	   a formatted Matrix message body to and from this format.

       o   String::Tagged::IRC - parse or build	IRC formatted messages and
	   convert bidirectionally to this format.

       o   String::Tagged::Terminal - build terminal control sequences for
	   message formatting and convert bidirectionally to this format.

       Paul Evans <>

perl v5.32.1			  2021-02-28	 String::Tagged::Formatting(3)


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