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Diffstat (limited to 'generic/tclOOScript.tcl')
| -rw-r--r-- | generic/tclOOScript.tcl | 456 |
1 files changed, 456 insertions, 0 deletions
diff --git a/generic/tclOOScript.tcl b/generic/tclOOScript.tcl new file mode 100644 index 0000000..a48eab5 --- /dev/null +++ b/generic/tclOOScript.tcl @@ -0,0 +1,456 @@ +# tclOOScript.h -- +# +# This file contains support scripts for TclOO. They are defined here so +# that the code can be definitely run even in safe interpreters; TclOO's +# core setup is safe. +# +# Copyright (c) 2012-2018 Donal K. Fellows +# Copyright (c) 2013 Andreas Kupries +# Copyright (c) 2017 Gerald Lester +# +# See the file "license.terms" for information on usage and redistribution of +# this file, and for a DISCLAIMER OF ALL WARRANTIES. + +::namespace eval ::oo { + ::namespace path {} + + # + # Commands that are made available to objects by default. + # + namespace eval Helpers { + ::namespace path {} + + # ------------------------------------------------------------------ + # + # callback, mymethod -- + # + # Create a script prefix that calls a method on the current + # object. Same operation, two names. + # + # ------------------------------------------------------------------ + + proc callback {method args} { + list [uplevel 1 {::namespace which my}] $method {*}$args + } + + # Make the [callback] command appear as [mymethod] too. + namespace export callback + namespace eval tmp {namespace import ::oo::Helpers::callback} + namespace export -clear + rename tmp::callback mymethod + namespace delete tmp + + # ------------------------------------------------------------------ + # + # classvariable -- + # + # Link to a variable in the class of the current object. + # + # ------------------------------------------------------------------ + + proc classvariable {name args} { + # Get a reference to the class's namespace + set ns [info object namespace [uplevel 1 {self class}]] + # Double up the list of variable names + foreach v [list $name {*}$args] { + if {[string match *(*) $v]} { + set reason "can't create a scalar variable that looks like an array element" + return -code error -errorcode {TCL UPVAR LOCAL_ELEMENT} \ + [format {bad variable name "%s": %s} $v $reason] + } + if {[string match *::* $v]} { + set reason "can't create a local variable with a namespace separator in it" + return -code error -errorcode {TCL UPVAR INVERTED} \ + [format {bad variable name "%s": %s} $v $reason] + } + lappend vs $v $v + } + # Lastly, link the caller's local variables to the class's variables + tailcall namespace upvar $ns {*}$vs + } + + # ------------------------------------------------------------------ + # + # link -- + # + # Make a command that invokes a method on the current object. + # The name of the command and the name of the method match by + # default. + # + # ------------------------------------------------------------------ + + proc link {args} { + set ns [uplevel 1 {::namespace current}] + foreach link $args { + if {[llength $link] == 2} { + lassign $link src dst + } elseif {[llength $link] == 1} { + lassign $link src + set dst $src + } else { + return -code error -errorcode {TCLOO CMDLINK FORMAT} \ + "bad link description; must only have one or two elements" + } + if {![string match ::* $src]} { + set src [string cat $ns :: $src] + } + interp alias {} $src {} ${ns}::my $dst + trace add command ${ns}::my delete [list \ + ::oo::UnlinkLinkedCommand $src] + } + return + } + } + + # ---------------------------------------------------------------------- + # + # UnlinkLinkedCommand -- + # + # Callback used to remove linked command when the underlying mechanism + # that supports it is deleted. + # + # ---------------------------------------------------------------------- + + proc UnlinkLinkedCommand {cmd args} { + if {[namespace which $cmd] ne {}} { + rename $cmd {} + } + } + + # ---------------------------------------------------------------------- + # + # DelegateName -- + # + # Utility that gets the name of the class delegate for a class. It's + # trivial, but makes working with them much easier as delegate names are + # intentionally hard to create by accident. + # + # ---------------------------------------------------------------------- + + proc DelegateName {class} { + string cat [info object namespace $class] {:: oo ::delegate} + } + + # ---------------------------------------------------------------------- + # + # MixinClassDelegates -- + # + # Support code called *after* [oo::define] inside the constructor of a + # class that patches in the appropriate class delegates. + # + # ---------------------------------------------------------------------- + + proc MixinClassDelegates {class} { + if {![info object isa class $class]} { + return + } + set delegate [DelegateName $class] + if {![info object isa class $delegate]} { + return + } + foreach c [info class superclass $class] { + set d [DelegateName $c] + if {![info object isa class $d]} { + continue + } + define $delegate superclass -append $d + } + objdefine $class mixin -append $delegate + } + + # ---------------------------------------------------------------------- + # + # UpdateClassDelegatesAfterClone -- + # + # Support code that is like [MixinClassDelegates] except for when a + # class is cloned. + # + # ---------------------------------------------------------------------- + + proc UpdateClassDelegatesAfterClone {originObject targetObject} { + # Rebuild the class inheritance delegation class + set originDelegate [DelegateName $originObject] + set targetDelegate [DelegateName $targetObject] + if { + [info object isa class $originDelegate] + && ![info object isa class $targetDelegate] + } then { + copy $originDelegate $targetDelegate + objdefine $targetObject mixin -set \ + {*}[lmap c [info object mixin $targetObject] { + if {$c eq $originDelegate} {set targetDelegate} {set c} + }] + } + } + + # ---------------------------------------------------------------------- + # + # oo::define::classmethod -- + # + # Defines a class method. See define(n) for details. + # + # Note that the ::oo::define namespace is semi-public and a bit weird + # anyway, so we don't regard the namespace path as being under control: + # fully qualified names are used for everything. + # + # ---------------------------------------------------------------------- + + proc define::classmethod {name {args {}} {body {}}} { + # Create the method on the class if the caller gave arguments and body + ::set argc [::llength [::info level 0]] + ::if {$argc == 3} { + ::return -code error -errorcode {TCL WRONGARGS} [::format \ + {wrong # args: should be "%s name ?args body?"} \ + [::lindex [::info level 0] 0]] + } + ::set cls [::uplevel 1 self] + ::if {$argc == 4} { + ::oo::define [::oo::DelegateName $cls] method $name $args $body + } + # Make the connection by forwarding + ::tailcall forward $name myclass $name + } + + # ---------------------------------------------------------------------- + # + # oo::define::initialise, oo::define::initialize -- + # + # Do specific initialisation for a class. See define(n) for details. + # + # Note that the ::oo::define namespace is semi-public and a bit weird + # anyway, so we don't regard the namespace path as being under control: + # fully qualified names are used for everything. + # + # ---------------------------------------------------------------------- + + proc define::initialise {body} { + ::set clsns [::info object namespace [::uplevel 1 self]] + ::tailcall apply [::list {} $body $clsns] + } + + # Make the [initialise] definition appear as [initialize] too + namespace eval define { + ::namespace export initialise + ::namespace eval tmp {::namespace import ::oo::define::initialise} + ::namespace export -clear + ::rename tmp::initialise initialize + ::namespace delete tmp + } + + # ---------------------------------------------------------------------- + # + # Slot -- + # + # The class of slot operations, which are basically lists at the low + # level of TclOO; this provides a more consistent interface to them. + # + # ---------------------------------------------------------------------- + + define Slot { + # ------------------------------------------------------------------ + # + # Slot Get -- + # + # Basic slot getter. Retrieves the contents of the slot. + # Particular slots must provide concrete non-erroring + # implementation. + # + # ------------------------------------------------------------------ + + method Get {} { + return -code error -errorcode {TCLOO ABSTRACT_SLOT} "unimplemented" + } + + # ------------------------------------------------------------------ + # + # Slot Set -- + # + # Basic slot setter. Sets the contents of the slot. Particular + # slots must provide concrete non-erroring implementation. + # + # ------------------------------------------------------------------ + + method Set list { + return -code error -errorcode {TCLOO ABSTRACT_SLOT} "unimplemented" + } + + # ------------------------------------------------------------------ + # + # Slot Resolve -- + # + # Helper that lets a slot convert a list of arguments of a + # particular type to their canonical forms. Defaults to doing + # nothing (suitable for simple strings). + # + # ------------------------------------------------------------------ + + method Resolve list { + return $list + } + + # ------------------------------------------------------------------ + # + # Slot -set, -append, -clear, --default-operation -- + # + # Standard public slot operations. If a slot can't figure out + # what method to call directly, it uses --default-operation. + # + # ------------------------------------------------------------------ + + method -set args { + set my [namespace which my] + set args [lmap a $args {uplevel 1 [list $my Resolve $a]}] + tailcall my Set $args + } + method -append args { + set my [namespace which my] + set args [lmap a $args {uplevel 1 [list $my Resolve $a]}] + set current [uplevel 1 [list $my Get]] + tailcall my Set [list {*}$current {*}$args] + } + method -clear {} {tailcall my Set {}} + method -prepend args { + set my [namespace which my] + set args [lmap a $args {uplevel 1 [list $my Resolve $a]}] + set current [uplevel 1 [list $my Get]] + tailcall my Set [list {*}$args {*}$current] + } + method -remove args { + set my [namespace which my] + set args [lmap a $args {uplevel 1 [list $my Resolve $a]}] + set current [uplevel 1 [list $my Get]] + tailcall my Set [lmap val $current { + if {$val in $args} continue else {set val} + }] + } + + # Default handling + forward --default-operation my -append + method unknown {args} { + set def --default-operation + if {[llength $args] == 0} { + tailcall my $def + } elseif {![string match -* [lindex $args 0]]} { + tailcall my $def {*}$args + } + next {*}$args + } + + # Set up what is exported and what isn't + export -set -append -clear -prepend -remove + unexport unknown destroy + } + + # Set the default operation differently for these slots + objdefine define::superclass forward --default-operation my -set + objdefine define::mixin forward --default-operation my -set + objdefine objdefine::mixin forward --default-operation my -set + + # ---------------------------------------------------------------------- + # + # oo::object <cloned> -- + # + # Handler for cloning objects that clones basic bits (only!) of the + # object's namespace. Non-procedures, traces, sub-namespaces, etc. need + # more complex (and class-specific) handling. + # + # ---------------------------------------------------------------------- + + define object method <cloned> {originObject} { + # Copy over the procedures from the original namespace + foreach p [info procs [info object namespace $originObject]::*] { + set args [info args $p] + set idx -1 + foreach a $args { + if {[info default $p $a d]} { + lset args [incr idx] [list $a $d] + } else { + lset args [incr idx] [list $a] + } + } + set b [info body $p] + set p [namespace tail $p] + proc $p $args $b + } + # Copy over the variables from the original namespace + foreach v [info vars [info object namespace $originObject]::*] { + upvar 0 $v vOrigin + namespace upvar [namespace current] [namespace tail $v] vNew + if {[info exists vOrigin]} { + if {[array exists vOrigin]} { + array set vNew [array get vOrigin] + } else { + set vNew $vOrigin + } + } + } + # General commands, sub-namespaces and advancd variable config (traces, + # etc) are *not* copied over. Classes that want that should do it + # themselves. + } + + # ---------------------------------------------------------------------- + # + # oo::class <cloned> -- + # + # Handler for cloning classes, which fixes up the delegates. + # + # ---------------------------------------------------------------------- + + define class method <cloned> {originObject} { + next $originObject + # Rebuild the class inheritance delegation class + ::oo::UpdateClassDelegatesAfterClone $originObject [self] + } + + # ---------------------------------------------------------------------- + # + # oo::singleton -- + # + # A metaclass that is used to make classes that only permit one instance + # of them to exist. See singleton(n). + # + # ---------------------------------------------------------------------- + + class create singleton { + superclass class + variable object + unexport create createWithNamespace + method new args { + if {![info exists object] || ![info object isa object $object]} { + set object [next {*}$args] + ::oo::objdefine $object { + method destroy {} { + ::return -code error -errorcode {TCLOO SINGLETON} \ + "may not destroy a singleton object" + } + method <cloned> {originObject} { + ::return -code error -errorcode {TCLOO SINGLETON} \ + "may not clone a singleton object" + } + } + } + return $object + } + } + + # ---------------------------------------------------------------------- + # + # oo::abstract -- + # + # A metaclass that is used to make classes that can't be directly + # instantiated. See abstract(n). + # + # ---------------------------------------------------------------------- + + class create abstract { + superclass class + unexport create createWithNamespace new + } +} + +# Local Variables: +# mode: tcl +# c-basic-offset: 4 +# fill-column: 78 +# End: |