st: -args- how to flag when missing or too many arguments

[John Antonakis <John.Antonakis@unil.ch>]

Hi:

I am writing a program and would like Stata to return an error if an 
argument is missing or there are too many of them.

For example, if an argument is not an integer, the below will return an 
error:

  program define john, rclass
  version 12
  args no_vars df N chi

  if `no_vars'<0 | `df'<0 | `N'<0 | `chi'<0 {
  di in red "You have to use integers."
  exit 498
  }
end

Now, how do I make Stata display:

  di in red "Please enter data after the command john as follows: vars 
df N chi"

.....in cases where (a) there is a missing value (i.e., the user missed 
putting 4 numbers) and (b) if the user provides too many numbers (i.e., 
5 instead of 4).

Thanks.
J.

--
__________________________________________

John Antonakis
Professor of Organizational Behavior
Director, Ph.D. Program in Management

Faculty of Business and Economics
University of Lausanne
Internef #618
CH-1015 Lausanne-Dorigny
Switzerland
Tel ++41 (0)21 692-3438
Fax ++41 (0)21 692-3305
http://www.hec.unil.ch/people/jantonakis

Associate Editor
The Leadership Quarterly
__________________________________________

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