return - Return from a procedure
return ?-code code? ?-errorinfo info? ?-errorcode code? ?string?
Return immediately from the current procedure
(or top-level command or source command),
with string as the return value. If string is not specified then
an empty string will be returned as result.
In the usual case where the -code option isn't
specified the procedure will return normally (its completion
code will be TCL_OK).
However, the -code option may be used to generate an
exceptional return from the procedure.
Code may have any of the following values:
- ok
-
Normal return: same as if the option is omitted.
- error
-
Error return: same as if the error command were used to
terminate the procedure, except for handling of errorInfo
and errorCode variables (see below).
- return
-
The current procedure will return with a completion code of
TCL_RETURN, so that the procedure that invoked it will return
also.
- break
-
The current procedure will return with a completion code of
TCL_BREAK, which will terminate the innermost nested loop in
the code that invoked the current procedure.
- continue
-
The current procedure will return with a completion code of
TCL_CONTINUE, which will terminate the current iteration of
the innermost nested loop in the code that invoked the current
procedure.
- value
-
Value must be an integer; it will be returned as the
completion code for the current procedure.
The -code option is rarely used.
It is provided so that procedures that implement
new control structures can reflect exceptional conditions back to
their callers.
Two additional options, -errorinfo and -errorcode,
may be used to provide additional information during error
returns.
These options are ignored unless code is error.
The -errorinfo option specifies an initial stack
trace for the errorInfo variable; if it is not specified then
the stack trace left in errorInfo will include the call to
the procedure and higher levels on the stack but it will not include
any information about the context of the error within the procedure.
Typically the info value is supplied from the value left
in errorInfo after a catch command trapped an error within
the procedure.
If the -errorcode option is specified then code provides
a value for the errorCode variable.
If the option is not specified then errorCode will
default to NONE.
break, continue, error, procedure, return
Copyright © 1993 The Regents of the University of California.
Copyright © 1994-1996 Sun Microsystems, Inc.
Copyright © 1995, 1996 Roger E. Critchlow Jr.