------------------------------------------------ On 28 Aug 2003 16:17:21 -0400, K Old <[EMAIL PROTECTED]> wrote:
> Hello everyone, > > Having been a Perl programmer for several years now I have become > accustom to using the following as my normal "start" of any Perl script: > > #!/usr/bin/perl > use warnings; > use strict; > > Randal Schwartz uses this: > > #!/usr/bin/perl -w > use strict; > $|++; > > Is there any difference between the -w and "use warnings" declaration? The one difference that I am aware of is the scoping. -w applies warnings to *all* code executed, whereas use warnings is file scoped (I believe) so that if you are working with a number of different modules that might cause warnings to be issued you will not see them under the 'use' method, but under -w you will. I prefer this because it gives me more direct control, but as the other poster mentioned I am only dealing with 5.6.0 and newer interpreters these days... > I know that both turn on warnings and the -w is commonly used at the > command line, but was just curious as to if one was "better" than the other. > > The posting a few weeks ago about "for" vs. "foreach" was interesting and got > me thinking about warnings. > > One other item, Randal uses $|++; to "turn off the buffering for STDOUT". > What exactly is buffering of standard output? > Its actually buffering of the currently selected file handle which is usually STDOUT. Output is buffered until there is a "significant" amount so that the relatively expensive output process doesn't happen over and over. Though in most cases these days I doubt it has a "significant" negative performance impact. Usually I leave things alone until I need them, but to each their own, and I think it is safe to assume Randal knows what he is doing :-). http://danconia.org -- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
