- Publicity: Public Only All
10-recreation-procs.tcl
XOTcl functionality for handling recreation of objects Support for the recreation of classes objects without destroying foreign references. Normally, when a class definition is reloaded, the class is destroyed and created again with the same name. During the destruction of a class several references to this class are removed (e.g. in a class hierarchy, the relation from instances to this class, etc.). XOTcl provides support for altering this behavior through the recreate method.
- Location:
- packages/xotcl-core/tcl/10-recreation-procs.tcl
- Created:
- 2005-05-13
- Author:
- Gustaf Neumann <neumann@wu-wien.ac.at>
- CVS Identification:
$Id: 10-recreation-procs.tcl,v 1.15 2024/09/11 06:15:56 gustafn Exp $
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::xo::library doc { XOTcl functionality for handling recreation of objects Support for the recreation of classes objects without destroying foreign references. Normally, when a class definition is reloaded, the class is destroyed and created again with the same name. During the destruction of a class several references to this class are removed (e.g. in a class hierarchy, the relation from instances to this class, etc.). XOTcl provides support for altering this behavior through the recreate method. @author Gustaf Neumann (neumann@wu-wien.ac.at) @creation-date 2005-05-13 @cvs-id $Id: 10-recreation-procs.tcl,v 1.15 2024/09/11 06:15:56 gustafn Exp $ } if {![::xotcl::Object isclass ::xotcl::RecreationClass]} { ::xotcl::Class create ::xotcl::RecreationClass -ad_doc { <p>This meta-class controls the behavior of classes (and optionally their instances), when the classes (or their instances) are overwritten by same named new objects; we call this situation a recreate of an object.</p> <p>Normally, when files with e.g. class definitions are sourced, the classes and objects are newly defined. When e.g. class definitions exists already in this file, these classes are deleted first before they are newly created. When a class is deleted, the instances of this class are changed into instances of class ::xotcl::Object. </p> <p>This can be a problem when the class instances are not reloaded and when they should survife the redefinition with the same class relationships. Therefore, we define a meta class RecreationClass, which can be used to parameterize the behavior on redefinitions. Alternatively, Classes or objects could provide their own recreate methods.</p> <p>Per default, this meta-class handles only the class redefinition case and does only a reconfigure on the class object (in order to get e.g. ad_doc updated).</p> The following parameters are defined: <ul> <li><b>reconfigure:</b> reconfigure class (default 1) <li><b>reinit:</b> run init after configure for this class (default unset) <li><b>instrecreate:</b> handle recreate of class instances (default unset) When this flag is set to 0, instreconfigure and instreinit are ignored. <li><b>instreconfigure:</b> reconfigure instances of this class (default 1) <li><b>instreinit:</b> re-init instances of this class (default unset) </ul> } -parameter { {reconfigure 1} {reinit} {instrecreate} {instreconfigure 1} {instreinit} } -superclass ::xotcl::Class \ -instproc recreate {obj args} { #:log "### recreateclass instproc $obj <$args>" # the minimal reconfiguration is to set the class and remove methods $obj class [self] foreach p [$obj info procs] {$obj proc $p {} {}} if {![info exists :instrecreate]} { #:log "### no instrecreate for $obj <$args>" next return } if {[info exists :instreconfigure]} { # before we set defaults, we must unset vars foreach var [$obj info vars] {$obj unset $var} # set defaults and run configure $obj set_instance_vars_defaults $obj configure {*}$args #:log "### instproc recreate $obj + configure $args ..." } if {[info exists :instreinit]} { #:log "### instreinit for $obj <$args>" $obj init #:log "### instproc recreate $obj + init ..." } } -proc recreate {obj args} { #:log "### recreateclass proc $obj <$args>" # the minimal reconfiguration is to set the class and remove methods $obj class [self] foreach p [$obj info instprocs] {$obj instproc $p {} {}} if {[info exists :reconfigure]} { # before we set defaults, we must unset vars foreach var [$obj info vars] {$obj unset $var} # set defaults and run configure $obj set_instance_vars_defaults $obj configure {*}$args } if {[info exists :reinit]} { $obj init } } ::Serializer exportObjects { ::xotcl::RecreationClass } } set version [package require XOTcl] if {[string match "1.3.*" $version]} { Class ad_proc recreate {obj args} { The re-definition of recreate makes reloading of class definitions via apm possible, since the foreign keys of the class relations to these classes survive these calls. One can define specialized versions of this for certain classes or use ::xotcl::RecreationClass. Class proc recreate is called on the class level, while Class instproc recreate is called on the instance level. @param obj name of the object to be recreated @param args arguments passed to recreate (might contain parameters) } { # clean on the class level #:log "proc recreate $obj $args" foreach p [$obj info instprocs] {$obj instproc $p {} {}} $obj instmixin set {} $obj instfilter set {} next ; # clean next on object level } Class ad_instproc recreate {obj args} { The re-definition of recreate makes reloading of class definitions via apm possible, since the foreign keys of the class relations to these classes survive these calls. One can define specialized versions of this for certain classes or use ::xotcl::RecreationClass. Class proc recreate is called on the class level, while Class instproc recreate is called on the instance level. @param obj name of the object to be recreated @param args arguments passed to recreate (might contain parameters) } { # clean on the object level #:log "+++ instproc recreate $obj <$args> old class = [$obj info class], new class = [self]" $obj filter set {} $obj mixin set {} set cl [self] foreach p [$obj info commands] {$obj proc $p {} {}} foreach c [$obj info children] { :log "recreate destroy <$c destroy" $c destroy } foreach var [$obj info vars] { $obj unset $var } # set p new values $obj class $cl $obj set_instance_vars_defaults # we use uplevel to handle -volatile correctly set pos [:uplevel [list $obj configure $args]] if {"-init" ni $args} { incr pos -1 $obj init {*}[lrange $args 0 $pos] } } #::xotcl::Object instforward unset -objscope # ::xotcl::Object instforward unset ::Serializer exportMethods { ::xotcl::Class instproc recreate ::xotcl::Class proc recreate ::xotcl::Object instforward unset } } else { ns_log notice "-- softrecreate" ::xotcl::configure softrecreate true Class create RR -instproc recreate args { :log "-- [self args]"; next } -instproc create args { :log "-- [self args]"; next } #::xotcl::Class instmixin RR } ::xo::library source_dependent # # Local variables: # mode: tcl # tcl-indent-level: 2 # indent-tabs-mode: nil # End:
