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+'\"
+'\" Copyright (c) 2007 Donal K. Fellows
+'\"
+'\" See the file "license.terms" for information on usage and redistribution
+'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
+'\"
+.TH self n 0.1 TclOO "TclOO Commands"
+.so man.macros
+.BS
+'\" Note:  do not modify the .SH NAME line immediately below!
+.SH NAME
+self \- method call internal introspection
+.SH SYNOPSIS
+.nf
+package require TclOO
+
+\fBself\fR ?\fIsubcommand\fR?
+.fi
+.BE
+.SH DESCRIPTION
+The \fBself\fR command, which should only be used from within the context of a
+call to a method (i.e. inside a method, constructor or destructor body) is
+used to allow the method to discover information about how it was called. It
+takes an argument, \fIsubcommand\fR, that tells it what sort of information is
+actually desired; if omitted the result will be the same as if \fBself
+object\fR was invoked. The supported subcommands are:
+.TP
+\fBself call\fR
+.
+This returns a two-element list describing the method implementations used to
+implement the current call chain. The first element is the same as would be
+reported by \fBinfo object\fR \fBcall\fR for the current method (except that this
+also reports useful values from within constructors and destructors, whose
+names are reported as \fB<constructor>\fR and \fB<destructor>\fR
+respectively), and the second element is an index into the first element's
+list that indicates which actual implementation is currently executing (the
+first implementation to execute is always at index 0).
+.TP
+\fBself caller\fR
+.
+When the method was invoked from inside another object method, this subcommand
+returns a three element list describing the containing object and method. The
+first element describes the declaring object or class of the method, the
+second element is the name of the object on which the containing method was
+invoked, and the third element is the name of the method (with the strings
+\fB<constructor>\fR and \fB<destructor>\fR indicating constructors and
+destructors respectively).
+.TP
+\fBself class\fR
+.
+This returns the name of the class that the current method was defined within.
+Note that this will change as the chain of method implementations is traversed
+with \fBnext\fR, and that if the method was defined on an object then this
+will fail.
+.RS
+.PP
+If you want the class of the current object, you need to use this other
+construct:
+.PP
+.CS
+info object class [\fBself object\fR]
+.CE
+.RE
+.TP
+\fBself filter\fR
+.
+When invoked inside a filter, this subcommand returns a three element list
+describing the filter. The first element gives the name of the object or class
+that declared the filter (note that this may be different from the object or
+class that provided the implementation of the filter), the second element is
+either \fBobject\fR or \fBclass\fR depending on whether the declaring entity
+was an object or class, and the third element is the name of the filter.
+.TP
+\fBself method\fR
+.
+This returns the name of the current method (with the strings
+\fB<constructor>\fR and \fB<destructor>\fR indicating constructors and
+destructors respectively).
+.TP
+\fBself namespace\fR
+.
+This returns the name of the unique namespace of the object that the method
+was invoked upon.
+.TP
+\fBself next\fR
+.
+When invoked from a method that is not at the end of a call chain (i.e. where
+the \fBnext\fR command will invoke an actual method implementation), this
+subcommand returns a two element list describing the next element in the
+method call chain; the first element is the name of the class or object that
+declares the next part of the call chain, and the second element is the name
+of the method (with the strings \fB<constructor>\fR and \fB<destructor>\fR
+indicating constructors and destructors respectively). If invoked from a
+method that is at the end of a call chain, this subcommand returns the empty
+string.
+.TP
+\fBself object\fR
+.
+This returns the name of the object that the method was invoked upon.
+.TP
+\fBself target\fR
+.
+When invoked inside a filter implementation, this subcommand returns a two
+element list describing the method being filtered. The first element will be
+the name of the declarer of the method, and the second element will be the
+actual name of the method.
+.SH EXAMPLES
+.PP
+This example shows basic use of \fBself\fR to provide information about the
+current object:
+.PP
+.CS
+oo::class create c {
+    method foo {} {
+        puts "this is the [\fBself\fR] object"
+    }
+}
+c create a
+c create b
+a foo                \fI\(-> prints "this is the ::a object"\fR
+b foo                \fI\(-> prints "this is the ::b object"\fR
+.CE
+.PP
+This demonstrates what a method call chain looks like, and how traversing
+along it changes the index into it:
+.PP
+.CS
+oo::class create c {
+    method x {} {
+        puts "Cls: [\fBself call\fR]"
+    }
+}
+c create a
+oo::objdefine a {
+    method x {} {
+        puts "Obj: [\fBself call\fR]"
+        next
+        puts "Obj: [\fBself call\fR]"
+    }
+}
+a x     \fI\(-> Obj: {{method x object method} {method x ::c method}} 0\fR
+        \fI\(-> Cls: {{method x object method} {method x ::c method}} 1\fR
+        \fI\(-> Obj: {{method x object method} {method x ::c method}} 0\fR
+.CE
+.SH "SEE ALSO"
+info(n), next(n)
+.SH KEYWORDS
+call, introspection, object
+.\" Local variables:
+.\" mode: nroff
+.\" fill-column: 78
+.\" End: