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Tcl_WrongNumArgs(3tcl) Tcl Library Procedures Tcl_WrongNumArgs(3tcl)
 


NAME

Tcl_WrongNumArgs - generate standard error message for wrong number of arguments

SYNOPSIS


#include <tcl.h>


Tcl_WrongNumArgs(interp, objc, objv, message)



ARGUMENTS



  
Tcl_Interp interp (in)

  
Interpreter in which error will be reported: error message gets stored in
      its result value.





  
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.
    
    

    
 

  




DESCRIPTION

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 value 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 value 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 values in the objv array may be abbreviations for a
  subcommand. The command Tcl_GetIndexFromObj will convert the
  abbreviated string value 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, let us assume that bar is actually
  an abbreviation for barfly and the value 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"





SEE ALSO

Tcl_GetIndexFromObj(3tcl)

KEYWORDS

command, error message, wrong number of arguments



  

    8.0
    Tcl