On 3/23/06, Christopher Spears <[EMAIL PROTECTED]> wrote:
> I've been reading the Intermediate Perl book and am
> trying to solve one of the exercises. I wrote a
> script that takes input from the keyboard and uses the
> input as a regular expression to search for files in a
> directory. If the script finds a match, the filename
> is printed out.
>
> #!/usr/bin/perl -w
> use strict;
>
> print "Enter a regular expression: ";
> chomp(my $pattern = <STDIN>);
>
> my $some_dir = "./ex2";
> opendir(DIR, $some_dir) || die "Can't open $some_dir:
> $!";
> my @filenames = readdir(DIR);
>
> foreach (@filenames) {
> if (eval {$_ =~ /$pattern/} ) {
> print $_ . "\n";
> }
> print "Continuing after error: $@" if $@;
> }
>
> I want the program to keep asking the user for a
> pattern until an empty string is entered. I
> remembered how to do this once, but I am returning to
> Perl after learning another language. I need to jog
> my memory!
>
<> will do what you're looking for, or <STDIN> if you prefer.:
my $some_dir = "./ex2";
opendir(DIR, $some_dir) || die "Can't open $some_dir: $!\n";
my @filenames = readdir(DIR);
while ( chomp(my $pattern = <>) ) {
last if $pattern =~ /^\s*$/;
foreach (@filenames) {
if (eval {$_ =~ /$pattern/} ) {
print $_ . "\n";
}
print "Continuing after error: $@" if $@;
}
}
If you're willing to just go with the standard EOF (ctrl-d on most
platforms), you don't even need to test the return value. STDIN/<>
close automatically when they encounter EOF and the loop will exit.
-- jay
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