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ActiveTcl User Guide |
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Tcl_WrongNumArgs - generate standard error message for wrong number
of arguments
#include <tcl.h>
Tcl_WrongNumArgs(interp, objc, objv, message)
- Tcl_Interp interp (in)
- Interpreter in which error will be reported: error message gets
stored in its result object.
- int objc (in)
- Number of leading arguments from objv to include in
error message.
- Tcl_Obj *CONST objv[] (in)
- Arguments to command that had the wrong number of
arguments.
- CONST char *message (in)
- Additional error information to print after leading arguments
from objv. This typically gives the acceptable syntax of the
command. This argument may be NULL.
Tcl_WrongNumArgs is a utility procedure that is invoked by
command procedures when they discover that they have received the
wrong number of arguments. Tcl_WrongNumArgs generates a
standard error message and stores it in the result object of
interp. The message includes the objc initial
elements of objv plus message. For example, if
objv consists of the values foo and bar,
objc is 1, and message is ``fileName count''
then interp's result object will be set to the following
string:
wrong # args: should be "foo fileName count"
If objc is 2, the result will be set to the following
string:
wrong # args: should be "foo bar fileName count"
Objc is usually 1, but may be 2 or more for commands like
string and the Tk widget
commands, which use the first argument as a subcommand.
Some of the objects in the objv array may be
abbreviations for a subcommand. The command Tcl_GetIndexFromObj will convert
the abbreviated string object into an indexObject. If an
error occurs in the parsing of the subcommand we would like to use
the full subcommand name rather than the abbreviation. If the
Tcl_WrongNumArgs command finds any indexObjects in
the objv array it will use the full subcommand name in the
error message instead of the abbreviated name that was originally
passed in. Using the above example, lets assume that bar is
actually an abbreviation for barfly and the object is now an
indexObject because it was passed to Tcl_GetIndexFromObj. In this case
the error message would be:
wrong # args: should be "foo barfly fileName count"
Tcl_GetIndexFromObj
command, error message, wrong number of
arguments
Copyright © 1994-1997 Sun Microsystems, Inc.
Copyright © 1995-1997 Roger E. Critchlow Jr.