precedence: two functions on one line

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

I'm trying to fill @files with:

#$files[0] = '/usr/local/bin/foobar/a.html'
#$files[1] = '/usr/local/bin/foobar/b.html'
#$files[2] = '/usr/local/bin/foobar/c.html'
#$files[3] = '/usr/local/bin/foobar/d.html'
#$files[4] = '/usr/local/bin/foobar/e.html'
#$files[5] = '/usr/local/bin/foobar/f.html'
[download]

here's the code:

$tracker =
<<EOQ;
a.html<br>
b.html<br>
c.html<br>
d.html<br>
e.html<br>
f.html<br>
EOQ
 
$path = "/usr/local/bin/foobar/";
[download]

Splitting works fine

@ttt = split /<br>\n/, $tracker;
 
for (@ttt) {
    print "$_\n";
}
[download]

My Question:

Should I be trying to do this by splitting and joining at once or is it better to do it in two separate calls? I guess I need to parenthesize things?

p220 of the Camel book 2nd ed. has this line:

print join ':', split / */, 'hi there';
[download]

Can I do something similar?

This part doesn't work yet:

@files = join split /<br>\n/, $tracker, $path;
 
foreach (@files) {
    print "$_\n"
}
[download]

Thanks!

Edit ar0n 2001-07-27 -- fixed formatting

Comment on precedence: two functions on one line Select or Download Code

Replies are listed 'Best First'.
Re: precedence: two functions on one line by bwana147 (Pilgrim) on Jul 27, 2001 at 18:38 UTC
Parentheses are mostly harmless, so you should use them when in doubt, or even when not in doubt, just to make things plain and visible. Now, as for your problem: `$path = "/usr/local/bin/foobar/"; @file = map { "$path/$_.html" } qw/ a b c d e f /;` [download] --bwana147	[reply] [d/l]
Re: Re: precedence: two functions on one line by kingman (Scribe) on Jul 27, 2001 at 18:59 UTC
I can't change the data as this is part of a larger application that expects $tracker to be a scalar. However, This variation on what you posted does exactly what I want, and on a single line too! `@files = map { "$path$_" } split /<br>\n/, $tracker;` [download] Must go meditate on the mysteries of the map function. Thanks!	[reply] [d/l]
Re: Re: Re: precedence: two functions on one line by andye (Curate) on Jul 27, 2001 at 19:14 UTC
map's great. Here's another example, to aid the old meditations: `$tracker = join "", map {"$_.html<br>\n"} ('a'..'f');` [download] - although frankly it's more readable as a here doc! andy.	[reply] [d/l]
Re: precedence: two functions on one line by earthboundmisfit (Chaplain) on Jul 27, 2001 at 18:38 UTC
Why not simply declare $tracker in list context? `@tracker = qw(a.html b.html c.html d.html e.html f.html);` [download] You can then use this array as a seed for opening and slurping each file to @files.	[reply] [d/l]
Re: precedence: two functions on one line by iakobski (Pilgrim) on Jul 27, 2001 at 18:38 UTC
You appear to have left out the first argument to join, it should be the character you want to put between each item you `join`. Use a null string if you just want to join everything together. -- iakobski	[reply] [d/l]
Re: Re: precedence: two functions on one line by kingman (Scribe) on Jul 27, 2001 at 18:45 UTC
The first argument to join is supposed to be `split /<br>\n/, $tracker` [download] The second arg is supposed to be: `$path` [download]	[reply] [d/l] [select]
Re: precedence: two functions on one line by runrig (Abbot) on Jul 27, 2001 at 18:55 UTC
You forgot the ":" argument to join, and you would do well with a map: `@files = join ":", map { "$path/$_" } split /<br>\n/, $tracker;` [download]	[reply] [d/l]


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