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diff --git a/upstream/debian-unstable/man3/Class::Struct.3perl b/upstream/debian-unstable/man3/Class::Struct.3perl new file mode 100644 index 00000000..b0a1401d --- /dev/null +++ b/upstream/debian-unstable/man3/Class::Struct.3perl @@ -0,0 +1,455 @@ +.\" -*- mode: troff; coding: utf-8 -*- +.\" Automatically generated by Pod::Man 5.01 (Pod::Simple 3.43) +.\" +.\" Standard preamble: +.\" ======================================================================== +.de Sp \" Vertical space (when we can't use .PP) +.if t .sp .5v +.if n .sp +.. +.de Vb \" Begin verbatim text +.ft CW +.nf +.ne \\$1 +.. +.de Ve \" End verbatim text +.ft R +.fi +.. +.\" \*(C` and \*(C' are quotes in nroff, nothing in troff, for use with C<>. +.ie n \{\ +. ds C` "" +. ds C' "" +'br\} +.el\{\ +. ds C` +. ds C' +'br\} +.\" +.\" Escape single quotes in literal strings from groff's Unicode transform. +.ie \n(.g .ds Aq \(aq +.el .ds Aq ' +.\" +.\" If the F register is >0, we'll generate index entries on stderr for +.\" titles (.TH), headers (.SH), subsections (.SS), items (.Ip), and index +.\" entries marked with X<> in POD. Of course, you'll have to process the +.\" output yourself in some meaningful fashion. +.\" +.\" Avoid warning from groff about undefined register 'F'. +.de IX +.. +.nr rF 0 +.if \n(.g .if rF .nr rF 1 +.if (\n(rF:(\n(.g==0)) \{\ +. if \nF \{\ +. de IX +. tm Index:\\$1\t\\n%\t"\\$2" +.. +. if !\nF==2 \{\ +. nr % 0 +. nr F 2 +. \} +. \} +.\} +.rr rF +.\" ======================================================================== +.\" +.IX Title "Class::Struct 3perl" +.TH Class::Struct 3perl 2024-01-12 "perl v5.38.2" "Perl Programmers Reference Guide" +.\" For nroff, turn off justification. Always turn off hyphenation; it makes +.\" way too many mistakes in technical documents. +.if n .ad l +.nh +.SH NAME +Class::Struct \- declare struct\-like datatypes as Perl classes +.SH SYNOPSIS +.IX Header "SYNOPSIS" +.Vb 5 +\& use Class::Struct; +\& # declare struct, based on array: +\& struct( CLASS_NAME => [ ELEMENT_NAME => ELEMENT_TYPE, ... ]); +\& # declare struct, based on hash: +\& struct( CLASS_NAME => { ELEMENT_NAME => ELEMENT_TYPE, ... }); +\& +\& package CLASS_NAME; +\& use Class::Struct; +\& # declare struct, based on array, implicit class name: +\& struct( ELEMENT_NAME => ELEMENT_TYPE, ... ); +\& +\& # Declare struct at compile time +\& use Class::Struct CLASS_NAME => [ELEMENT_NAME => ELEMENT_TYPE, ...]; +\& use Class::Struct CLASS_NAME => {ELEMENT_NAME => ELEMENT_TYPE, ...}; +\& +\& # declare struct at compile time, based on array, implicit +\& # class name: +\& package CLASS_NAME; +\& use Class::Struct ELEMENT_NAME => ELEMENT_TYPE, ... ; +\& +\& package Myobj; +\& use Class::Struct; +\& # declare struct with four types of elements: +\& struct( s => \*(Aq$\*(Aq, a => \*(Aq@\*(Aq, h => \*(Aq%\*(Aq, c => \*(AqMy_Other_Class\*(Aq ); +\& +\& my $obj = Myobj\->new; # constructor +\& +\& # scalar type accessor: +\& my $element_value = $obj\->s; # element value +\& $obj\->s(\*(Aqnew value\*(Aq); # assign to element +\& +\& # array type accessor: +\& my $ary_ref = $obj\->a; # reference to whole array +\& my $ary_element_value = $obj\->a(2); # array element value +\& $obj\->a(2, \*(Aqnew value\*(Aq); # assign to array element +\& +\& # hash type accessor: +\& my $hash_ref = $obj\->h; # reference to whole hash +\& my $hash_element_value = $obj\->h(\*(Aqx\*(Aq); # hash element value +\& $obj\->h(\*(Aqx\*(Aq, \*(Aqnew value\*(Aq); # assign to hash element +\& +\& # class type accessor: +\& my $element_value = $obj\->c; # object reference +\& $obj\->c\->method(...); # call method of object +\& $obj\->c(new My_Other_Class); # assign a new object +.Ve +.SH DESCRIPTION +.IX Header "DESCRIPTION" +\&\f(CW\*(C`Class::Struct\*(C'\fR exports a single function, \f(CW\*(C`struct\*(C'\fR. +Given a list of element names and types, and optionally +a class name, \f(CW\*(C`struct\*(C'\fR creates a Perl 5 class that implements +a "struct-like" data structure. +.PP +The new class is given a constructor method, \f(CW\*(C`new\*(C'\fR, for creating +struct objects. +.PP +Each element in the struct data has an accessor method, which is +used to assign to the element and to fetch its value. The +default accessor can be overridden by declaring a \f(CW\*(C`sub\*(C'\fR of the +same name in the package. (See Example 2.) +.PP +Each element's type can be scalar, array, hash, or class. +.ie n .SS "The struct() function" +.el .SS "The \f(CWstruct()\fP function" +.IX Subsection "The struct() function" +The \f(CW\*(C`struct\*(C'\fR function has three forms of parameter-list. +.PP +.Vb 3 +\& struct( CLASS_NAME => [ ELEMENT_LIST ]); +\& struct( CLASS_NAME => { ELEMENT_LIST }); +\& struct( ELEMENT_LIST ); +.Ve +.PP +The first and second forms explicitly identify the name of the +class being created. The third form assumes the current package +name as the class name. +.PP +An object of a class created by the first and third forms is +based on an array, whereas an object of a class created by the +second form is based on a hash. The array-based forms will be +somewhat faster and smaller; the hash-based forms are more +flexible. +.PP +The class created by \f(CW\*(C`struct\*(C'\fR must not be a subclass of another +class other than \f(CW\*(C`UNIVERSAL\*(C'\fR. +.PP +It can, however, be used as a superclass for other classes. To facilitate +this, the generated constructor method uses a two-argument blessing. +Furthermore, if the class is hash-based, the key of each element is +prefixed with the class name (see \fIPerl Cookbook\fR, Recipe 13.12). +.PP +A function named \f(CW\*(C`new\*(C'\fR must not be explicitly defined in a class +created by \f(CW\*(C`struct\*(C'\fR. +.PP +The \fIELEMENT_LIST\fR has the form +.PP +.Vb 1 +\& NAME => TYPE, ... +.Ve +.PP +Each name-type pair declares one element of the struct. Each +element name will be defined as an accessor method unless a +method by that name is explicitly defined; in the latter case, a +warning is issued if the warning flag (\fB\-w\fR) is set. +.SS "Class Creation at Compile Time" +.IX Subsection "Class Creation at Compile Time" +\&\f(CW\*(C`Class::Struct\*(C'\fR can create your class at compile time. The main reason +for doing this is obvious, so your class acts like every other class in +Perl. Creating your class at compile time will make the order of events +similar to using any other class ( or Perl module ). +.PP +There is no significant speed gain between compile time and run time +class creation, there is just a new, more standard order of events. +.SS "Element Types and Accessor Methods" +.IX Subsection "Element Types and Accessor Methods" +The four element types \-\- scalar, array, hash, and class \-\- are +represented by strings \-\- \f(CW\*(Aq$\*(Aq\fR, \f(CW\*(Aq@\*(Aq\fR, \f(CW\*(Aq%\*(Aq\fR, and a class name \-\- +optionally preceded by a \f(CW\*(Aq*\*(Aq\fR. +.PP +The accessor method provided by \f(CW\*(C`struct\*(C'\fR for an element depends +on the declared type of the element. +.ie n .IP "Scalar (\*(Aq$\*(Aq or \*(Aq*$\*(Aq)" 4 +.el .IP "Scalar (\f(CW\*(Aq$\*(Aq\fR or \f(CW\*(Aq*$\*(Aq\fR)" 4 +.IX Item "Scalar ($ or *$)" +The element is a scalar, and by default is initialized to \f(CW\*(C`undef\*(C'\fR +(but see "Initializing with new"). +.Sp +The accessor's argument, if any, is assigned to the element. +.Sp +If the element type is \f(CW\*(Aq$\*(Aq\fR, the value of the element (after +assignment) is returned. If the element type is \f(CW\*(Aq*$\*(Aq\fR, a reference +to the element is returned. +.ie n .IP "Array (\*(Aq@\*(Aq or \*(Aq*@\*(Aq)" 4 +.el .IP "Array (\f(CW\*(Aq@\*(Aq\fR or \f(CW\*(Aq*@\*(Aq\fR)" 4 +.IX Item "Array (@ or *@)" +The element is an array, initialized by default to \f(CW\*(C`()\*(C'\fR. +.Sp +With no argument, the accessor returns a reference to the +element's whole array (whether or not the element was +specified as \f(CW\*(Aq@\*(Aq\fR or \f(CW\*(Aq*@\*(Aq\fR). +.Sp +With one or two arguments, the first argument is an index +specifying one element of the array; the second argument, if +present, is assigned to the array element. If the element type +is \f(CW\*(Aq@\*(Aq\fR, the accessor returns the array element value. If the +element type is \f(CW\*(Aq*@\*(Aq\fR, a reference to the array element is +returned. +.Sp +As a special case, when the accessor is called with an array reference +as the sole argument, this causes an assignment of the whole array element. +The object reference is returned. +.ie n .IP "Hash (\*(Aq%\*(Aq or \*(Aq*%\*(Aq)" 4 +.el .IP "Hash (\f(CW\*(Aq%\*(Aq\fR or \f(CW\*(Aq*%\*(Aq\fR)" 4 +.IX Item "Hash (% or *%)" +The element is a hash, initialized by default to \f(CW\*(C`()\*(C'\fR. +.Sp +With no argument, the accessor returns a reference to the +element's whole hash (whether or not the element was +specified as \f(CW\*(Aq%\*(Aq\fR or \f(CW\*(Aq*%\*(Aq\fR). +.Sp +With one or two arguments, the first argument is a key specifying +one element of the hash; the second argument, if present, is +assigned to the hash element. If the element type is \f(CW\*(Aq%\*(Aq\fR, the +accessor returns the hash element value. If the element type is +\&\f(CW\*(Aq*%\*(Aq\fR, a reference to the hash element is returned. +.Sp +As a special case, when the accessor is called with a hash reference +as the sole argument, this causes an assignment of the whole hash element. +The object reference is returned. +.ie n .IP "Class (\*(AqClass_Name\*(Aq or \*(Aq*Class_Name\*(Aq)" 4 +.el .IP "Class (\f(CW\*(AqClass_Name\*(Aq\fR or \f(CW\*(Aq*Class_Name\*(Aq\fR)" 4 +.IX Item "Class (Class_Name or *Class_Name)" +The element's value must be a reference blessed to the named +class or to one of its subclasses. The element is not initialized +by default. +.Sp +The accessor's argument, if any, is assigned to the element. The +accessor will \f(CW\*(C`croak\*(C'\fR if this is not an appropriate object +reference. +.Sp +If the element type does not start with a \f(CW\*(Aq*\*(Aq\fR, the accessor +returns the element value (after assignment). If the element type +starts with a \f(CW\*(Aq*\*(Aq\fR, a reference to the element itself is returned. +.ie n .SS "Initializing with ""new""" +.el .SS "Initializing with \f(CWnew\fP" +.IX Subsection "Initializing with new" +\&\f(CW\*(C`struct\*(C'\fR always creates a constructor called \f(CW\*(C`new\*(C'\fR. That constructor +may take a list of initializers for the various elements of the new +struct. +.PP +Each initializer is a pair of values: \fIelement name\fR\f(CW\*(C` => \*(C'\fR\fIvalue\fR. +The initializer value for a scalar element is just a scalar value. The +initializer for an array element is an array reference. The initializer +for a hash is a hash reference. +.PP +The initializer for a class element is an object of the corresponding class, +or of one of it's subclasses, or a reference to a hash containing named +arguments to be passed to the element's constructor. +.PP +See Example 3 below for an example of initialization. +.SH EXAMPLES +.IX Header "EXAMPLES" +.IP "Example 1" 4 +.IX Item "Example 1" +Giving a struct element a class type that is also a struct is how +structs are nested. Here, \f(CW\*(C`Timeval\*(C'\fR represents a time (seconds and +microseconds), and \f(CW\*(C`Rusage\*(C'\fR has two elements, each of which is of +type \f(CW\*(C`Timeval\*(C'\fR. +.Sp +.Vb 1 +\& use Class::Struct; +\& +\& struct( Rusage => { +\& ru_utime => \*(AqTimeval\*(Aq, # user time used +\& ru_stime => \*(AqTimeval\*(Aq, # system time used +\& }); +\& +\& struct( Timeval => [ +\& tv_secs => \*(Aq$\*(Aq, # seconds +\& tv_usecs => \*(Aq$\*(Aq, # microseconds +\& ]); +\& +\& # create an object: +\& my $t = Rusage\->new(ru_utime=>Timeval\->new(), +\& ru_stime=>Timeval\->new()); +\& +\& # $t\->ru_utime and $t\->ru_stime are objects of type Timeval. +\& # set $t\->ru_utime to 100.0 sec and $t\->ru_stime to 5.0 sec. +\& $t\->ru_utime\->tv_secs(100); +\& $t\->ru_utime\->tv_usecs(0); +\& $t\->ru_stime\->tv_secs(5); +\& $t\->ru_stime\->tv_usecs(0); +.Ve +.IP "Example 2" 4 +.IX Item "Example 2" +An accessor function can be redefined in order to provide +additional checking of values, etc. Here, we want the \f(CW\*(C`count\*(C'\fR +element always to be nonnegative, so we redefine the \f(CW\*(C`count\*(C'\fR +accessor accordingly. +.Sp +.Vb 2 +\& package MyObj; +\& use Class::Struct; +\& +\& # declare the struct +\& struct ( \*(AqMyObj\*(Aq, { count => \*(Aq$\*(Aq, stuff => \*(Aq%\*(Aq } ); +\& +\& # override the default accessor method for \*(Aqcount\*(Aq +\& sub count { +\& my $self = shift; +\& if ( @_ ) { +\& die \*(Aqcount must be nonnegative\*(Aq if $_[0] < 0; +\& $self\->{\*(AqMyObj::count\*(Aq} = shift; +\& warn "Too many args to count" if @_; +\& } +\& return $self\->{\*(AqMyObj::count\*(Aq}; +\& } +\& +\& package main; +\& $x = new MyObj; +\& print "\e$x\->count(5) = ", $x\->count(5), "\en"; +\& # prints \*(Aq$x\->count(5) = 5\*(Aq +\& +\& print "\e$x\->count = ", $x\->count, "\en"; +\& # prints \*(Aq$x\->count = 5\*(Aq +\& +\& print "\e$x\->count(\-5) = ", $x\->count(\-5), "\en"; +\& # dies due to negative argument! +.Ve +.IP "Example 3" 4 +.IX Item "Example 3" +The constructor of a generated class can be passed a list +of \fIelement\fR=>\fIvalue\fR pairs, with which to initialize the struct. +If no initializer is specified for a particular element, its default +initialization is performed instead. Initializers for non-existent +elements are silently ignored. +.Sp +Note that the initializer for a nested class may be specified as +an object of that class, or as a reference to a hash of initializers +that are passed on to the nested struct's constructor. +.Sp +.Vb 1 +\& use Class::Struct; +\& +\& struct Breed => +\& { +\& name => \*(Aq$\*(Aq, +\& cross => \*(Aq$\*(Aq, +\& }; +\& +\& struct Cat => +\& [ +\& name => \*(Aq$\*(Aq, +\& kittens => \*(Aq@\*(Aq, +\& markings => \*(Aq%\*(Aq, +\& breed => \*(AqBreed\*(Aq, +\& ]; +\& +\& +\& my $cat = Cat\->new( name => \*(AqSocks\*(Aq, +\& kittens => [\*(AqMonica\*(Aq, \*(AqKenneth\*(Aq], +\& markings => { socks=>1, blaze=>"white" }, +\& breed => Breed\->new(name=>\*(Aqshort\-hair\*(Aq, cross=>1), +\& or: breed => {name=>\*(Aqshort\-hair\*(Aq, cross=>1}, +\& ); +\& +\& print "Once a cat called ", $cat\->name, "\en"; +\& print "(which was a ", $cat\->breed\->name, ")\en"; +\& print "had 2 kittens: ", join(\*(Aq and \*(Aq, @{$cat\->kittens}), "\en"; +.Ve +.SH "Author and Modification History" +.IX Header "Author and Modification History" +Modified by Damian Conway, 2001\-09\-10, v0.62. +.PP +.Vb 11 +\& Modified implicit construction of nested objects. +\& Now will also take an object ref instead of requiring a hash ref. +\& Also default initializes nested object attributes to undef, rather +\& than calling object constructor without args +\& Original over\-helpfulness was fraught with problems: +\& * the class\*(Aqs constructor might not be called \*(Aqnew\*(Aq +\& * the class might not have a hash\-like\-arguments constructor +\& * the class might not have a no\-argument constructor +\& * "recursive" data structures didn\*(Aqt work well: +\& package Person; +\& struct { mother => \*(AqPerson\*(Aq, father => \*(AqPerson\*(Aq}; +.Ve +.PP +Modified by Casey West, 2000\-11\-08, v0.59. +.PP +.Vb 1 +\& Added the ability for compile time class creation. +.Ve +.PP +Modified by Damian Conway, 1999\-03\-05, v0.58. +.PP +.Vb 1 +\& Added handling of hash\-like arg list to class ctor. +\& +\& Changed to two\-argument blessing in ctor to support +\& derivation from created classes. +\& +\& Added classname prefixes to keys in hash\-based classes +\& (refer to "Perl Cookbook", Recipe 13.12 for rationale). +\& +\& Corrected behaviour of accessors for \*(Aq*@\*(Aq and \*(Aq*%\*(Aq struct +\& elements. Package now implements documented behaviour when +\& returning a reference to an entire hash or array element. +\& Previously these were returned as a reference to a reference +\& to the element. +.Ve +.PP +Renamed to \f(CW\*(C`Class::Struct\*(C'\fR and modified by Jim Miner, 1997\-04\-02. +.PP +.Vb 8 +\& members() function removed. +\& Documentation corrected and extended. +\& Use of struct() in a subclass prohibited. +\& User definition of accessor allowed. +\& Treatment of \*(Aq*\*(Aq in element types corrected. +\& Treatment of classes as element types corrected. +\& Class name to struct() made optional. +\& Diagnostic checks added. +.Ve +.PP +Originally \f(CW\*(C`Class::Template\*(C'\fR by Dean Roehrich. +.PP +.Vb 10 +\& # Template.pm \-\-\- struct/member template builder +\& # 12mar95 +\& # Dean Roehrich +\& # +\& # changes/bugs fixed since 28nov94 version: +\& # \- podified +\& # changes/bugs fixed since 21nov94 version: +\& # \- Fixed examples. +\& # changes/bugs fixed since 02sep94 version: +\& # \- Moved to Class::Template. +\& # changes/bugs fixed since 20feb94 version: +\& # \- Updated to be a more proper module. +\& # \- Added "use strict". +\& # \- Bug in build_methods, was using @var when @$var needed. +\& # \- Now using my() rather than local(). +\& # +\& # Uses perl5 classes to create nested data types. +\& # This is offered as one implementation of Tom Christiansen\*(Aqs +\& # "structs.pl" idea. +.Ve |