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-rw-r--r--doc/unknown.n28
1 files changed, 14 insertions, 14 deletions
diff --git a/doc/unknown.n b/doc/unknown.n
index a5cbe6f..c258daa 100644
--- a/doc/unknown.n
+++ b/doc/unknown.n
@@ -14,22 +14,24 @@ unknown \- Handle attempts to use non-existent commands
.SH SYNOPSIS
\fBunknown \fIcmdName \fR?\fIarg arg ...\fR?
.BE
-
.SH DESCRIPTION
.PP
This command is invoked by the Tcl interpreter whenever a script
-tries to invoke a command that doesn't exist. The default implementation
+tries to invoke a command that does not exist. The default implementation
of \fBunknown\fR is a library procedure defined when Tcl initializes an
interpreter. You can override the default \fBunknown\fR to change its
-functionality. Note that there is no default implementation of
-\fBunknown\fR in a safe interpreter.
+functionality, or you can register a new handler for individual namespaces
+using the \fBnamespace unknown\fR command. Note that there is no default
+implementation of \fBunknown\fR in a safe interpreter.
.PP
If the Tcl interpreter encounters a command name for which there
-is not a defined command, then Tcl checks for the existence of
-a command named \fBunknown\fR.
-If there is no such command, then the interpreter returns an
-error.
-If the \fBunknown\fR command exists, then it is invoked with
+is not a defined command (in either the current namespace, or the
+global namespace), then Tcl checks for the existence of
+an unknown handler for the current namespace. By default, this
+handler is a command named \fB::unknown\fR. If there is no such
+command, then the interpreter returns an error.
+If the \fBunknown\fR command exists (or a new handler has been
+registered for the current namespace), then it is invoked with
arguments consisting of the fully-substituted name and arguments
for the original non-existent command.
The \fBunknown\fR command typically does things like searching
@@ -49,7 +51,7 @@ If the auto-load fails then \fBunknown\fR calls \fBauto_execok\fR
to see if there is an executable file by the name \fIcmd\fR.
If so, it invokes the Tcl \fBexec\fR command
with \fIcmd\fR and all the \fIargs\fR as arguments.
-If \fIcmd\fR can't be auto-executed, \fBunknown\fR checks to
+If \fIcmd\fR cannot be auto-executed, \fBunknown\fR checks to
see if the command was invoked at top-level and outside of any
script. If so, then \fBunknown\fR takes two additional steps.
First, it sees if \fIcmd\fR has one of the following three forms:
@@ -80,12 +82,10 @@ rename \fBunknown\fR _original_unknown
# Provide our own implementation
proc \fBunknown\fR args {
puts stderr "WARNING: unknown command: $args"
- uplevel 1 [list _original_unknown {expand}$args]
+ uplevel 1 [list _original_unknown {*}$args]
}
.CE
-
.SH "SEE ALSO"
-info(n), proc(n), interp(n), library(n)
-
+info(n), proc(n), interp(n), library(n), namespace(n)
.SH KEYWORDS
error, non-existent command