Can Perl Turn A String Into A Virtual File?

sierrathedog04 has asked for the wisdom of the Perl Monks concerning the following question:

I have a script which works great when I read from a file:

open (MYFILE, 'mypath');
while (<MYFILE>){
#my code here
}
[download]

I would like to be able to use this same syntax when the text to be processed is in the form of a string rather than a file. Can I associate a string with a virtual filehandle? Ideally the syntax would be something like:

#magically turn $myString into a filehandle.
while (<MYSTRING>){
    #my code here
}
[download]

Comment on Can Perl Turn A String Into A Virtual File? Select or Download Code

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Re: Can Perl Turn A String Into A Virtual File? by Masem (Monsignor) on May 25, 2001 at 00:35 UTC
Look at the module IO::String, while allows you to treat a string as an IO::File handle, which act just like your typical perl file handles. Dr. Michael K. Neylon - mneylon-pm@masemware.com \|\| "You've left the lens cap of your mind on again, Pinky" - The Brain	[reply]
Re: Re: Can Perl Turn A String Into A Virtual File? by shotgunefx (Parson) on May 25, 2001 at 05:16 UTC
I believe it's named IO::Stringy. -Lee "To be civilized is to deny one's nature."	[reply]
(boo) Re: Can Perl Turn A String Into A Virtual File? by boo_radley (Parson) on May 25, 2001 at 00:27 UTC
figure out what your "virtual newlines" would be,and split on them, so you can go back to `while (@lines) {...}` [download] not very magical, but hey.	[reply] [d/l]
Re: Can Perl Turn A String Into A Virtual File? by Big Willy (Scribe) on May 25, 2001 at 00:59 UTC
If you're looking to be more ambiguous (bonus!), the way to go would be to implement as mentioned by the others: `while(@lines) { ... }` [download] Then, if you want to use a file, you can do `@lines = <MYFILE>;` [download] or for a string `@lines = split /\n/, $string;` [download] prior to executing the loop. Setting up a string to work via a file handle is a little extreme, unless you need it to work in both cases and the files you are working with are too large to be worth reading in in a single gulp. This is one of the things the IO::String is supposed to do, and the thing you would need to do to use the form you originally proposed. But IO::String, according to its documentation, does not yet have this feature implemented! So, unless have huge files, just go with the the way of the array.	[reply] [d/l] [select]
Re: Can Perl Turn A String Into A Virtual File? by bikeNomad (Priest) on May 25, 2001 at 10:21 UTC
Sure, you can use IO::Scalar: `use IO::Scalar; my $myString = "stuff here\nmore stuff"; my $fh = IO::Scalar->new(\$myString); while <$fh> { # yer code here }` [download]	[reply] [d/l]
Re: Can Perl Turn A String Into A Virtual File? by DBX (Pilgrim) on May 25, 2001 at 00:40 UTC
Anything after the `__DATA__` token can be read with the `<DATA>` filehandle, like: `while(<DATA>){ # do something } __DATA__ Process here, line 1 Process here some more, line 2` [download]	[reply] [d/l] [select]
Re: Can Perl Turn A String Into A Virtual File? by Anonymous Monk on May 25, 2001 at 04:01 UTC
`my $myString = "This is a test\nthis is only a test\n"; pipe(READER, WRITER); if(fork()) #should have some error checking { close(WRITER); while(<READER>) { print "I just read: $_"; } } else { close(READER); print WRITER $myString; close(WRITER); exit; }` [download]	[reply] [d/l]