They're two different things really -
foreach takes a list and iterates over the given list, whereas
while will keep looping until it's condition expression evaluates to false. In the first instance where you're using
foreach,
<FH> is evaluated in list context, as
foreach evaluates it's provided arguments in list context, which will then read until it reaches an
eof and then returns the lines that were read as a list. Whereas when you use a
while,
perl will auto-magically wrap your filehandle read with a check for
definedness e.g
perl -MO=Deparse -e 'while(<>) { }'
while (defined($_ = <ARGV>)) {
();
}
-e syntax OK
Then will continue looping until the filehandle reaches an
eof, so only ever reads in a line at a time. See.
perlsyn for more info on looping.
HTH
_________
broquaint
Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
Read Where should I post X? if you're not absolutely sure you're posting in the right place.
Please read these before you post! —
Posts may use any of the Perl Monks Approved HTML tags:
- a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
| |
For: |
|
Use: |
| & | | & |
| < | | < |
| > | | > |
| [ | | [ |
| ] | | ] |
Link using PerlMonks shortcuts! What shortcuts can I use for linking?
See Writeup Formatting Tips and other pages linked from there for more info.