----- Original Message ----- From: "Paul Johnson" <p...@pjcj.net> To: "Stanisław T. Findeisen" <sf181...@students.mimuw.edu.pl> Cc: beginners@perl.org Sent: Thursday, 12 March, 2009 19:27:02 GMT -07:00 US/Canada Mountain Subject: Re: use constant
On Thu, Mar 12, 2009 at 11:50:46PM +0100, "Stanisław T. Findeisen" wrote: > Is there any way to change the values of [scalar/array] constants > defined via "use constant" pragma? That seems a strange thing to want to do. But useful for redefining pi, or perhaps G, I suppose. In general the answer is no. But if you can live with a mandatory warning and the knowledge that you have lied to perl (and you understand the effects that brings, specifically with respect to constant propagation) then go ahead and do it. It's not a good idea, but it's not in perl's nature to pretend that she knows better than you, even if she does. If you want a constant that varies, can you not just use a variable? -- Paul Johnson - p...@pjcj.net http://www.pjcj.net -- I do this regularly redefine constants in my programs. I'm not sure if it's good practice but I do it. What I do is define a constant in most subroutines. The constant is called, strange enough, PROC_NM. I felt that because this was being defined local to each routine that I wasn't breaking all the rules I had been taught. I know I get a warning message each time I redefine it but to me it is a local constant not a variable. I don't define it in my helper routines so when they printout an error message and reference PROC_NM I know where they are called from. If anyone has a better idea I'd love to hear it. Suzanne. --------- Suzanne Aardema Systems Analyst/Programmer Applications Development Computing Services Athabasca University 1 University Drive Athabasca, AB T9S 3A3 ph: 780-421-2527 fax: 780-428-2464 email: suzan...@athabascau.ca __ This communication is intended for the use of the recipient to whom it is addressed, and may contain confidential, personal, and or privileged information. Please contact us immediately if you are not the intended recipient of this communication, and do not copy, distribute, or take action relying on it. Any communications received in error, or subsequent reply, should be deleted or destroyed. --- -- To unsubscribe, e-mail: beginners-unsubscr...@perl.org For additional commands, e-mail: beginners-h...@perl.org http://learn.perl.org/
