On Wed, Jan 07, 2004 at 06:00:51PM +0100, Jan Kesten wrote:
> # Datei lesen
> open DATEI, "<$dateiname" or die "$dateiname laesst sich nicht oeffnen\n";
Use the $! variable (man perlvar; perldoc perlvar; www.perldoc.com):
open DATEI, "<$dateiname" or die "Datei `$dateiname' laesst sich nicht oeffnen:
$!\n";
> @zeilen = <DATEI> or die "$dateiname ist nicht lesbar\n"
> close DATEI;
close DATEI or warn "Cannot close file `$dateiname': $!\n";
> # sortieren
You can sort just by reading:
@sorted_zeilen = sort <DATEI> or die $!;
> - ---- SNIP ----
>
> And the python way looks like this:
>
> # Datei lesen
> try:
> datei = open(dateiname, 'r')
> zeilen = datei.readlines()
> datei.close()
> except IOError:
> print dateiname, "ist nicht lesbar"
> sys.exit( 1 )
That's not what is above in perl. I understand especially: you
are saying that Python has exceptions. But Perl also has! Read about
`eval' in man perlfunc or `perldoc -f eval'. The advantidge of using
"die" for each part of code is that you can give more precise error
message, even more if combined with the `$!' variable. Above Python code
would be almost ekvivalently rewritten into Perl:
eval {
open DATEI, "<$dateiname" or die $!;
@zeilen = <DATEI> or die $!;
close DATEI;
}
die "Datei `$dateiname' ist nicht lesbar: [EMAIL PROTECTED]" if $@;
> Some other thing is that python knows about classes :-) But I do not
Perl also knows about classes (perldoc -f bless; man perlboot,
perltoot, perlobj).
> want to start a discussion about pro perl or python :-)
Nor want I, but be precise.
Best regards
Hans Ginzel
