alanm@cognos.UUCP (Alan Myrvold) (10/26/90)
Recently, I wrote a bit of a perl script that looked something
like this:
open(oct,"< October");
while (<oct>) {
print;
}
Even though the file October exists, nothing was printed. This
is due to my choice of oct as a filehandle, since oct is a built-in
function.
Why couldn't I have at least gotten a warning during the compile?
With perl's big collection of functions, I can't be the only one
making mistakes like this. Is it ever proper to use a function name
where a file handle is expected?
- Alan
---
Alan Myrvold 3755 Riverside Dr. uunet!mitel!cunews!cognos!alanm
Cognos Incorporated P.O. Box 9707 alanm@cognos.uucp
(613) 738-1440 x5530 Ottawa, Ontario
CANADA K1G 3Z4 lwall@jpl-devvax.JPL.NASA.GOV (Larry Wall) (10/27/90)
In article <8974@cognos.UUCP> alanm@cognos.UUCP (Alan Myrvold) writes:
: Recently, I wrote a bit of a perl script that looked something
: like this:
:
: open(oct,"< October");
: while (<oct>) {
: print;
: }
:
: Even though the file October exists, nothing was printed. This
: is due to my choice of oct as a filehandle, since oct is a built-in
: function.
:
: Why couldn't I have at least gotten a warning during the compile?
: With perl's big collection of functions, I can't be the only one
: making mistakes like this. Is it ever proper to use a function name
: where a file handle is expected?
Yes, it is. The above converts the octal value found in $_ to a decimal
value, then uses that number as the filehandle. Why you'd want to do
that is beyond me, but it's perfectly legal--the first argument of
open can be any expression yeilding a filehandle.
The manual suggests you use upper case for filehandles and labels. There
is a REASON for that...
Larry