--- Piers Cawley <[EMAIL PROTECTED]> wrote:
> Paul <[EMAIL PROTECTED]> writes:
> > BTW, this is another use of the same sort of trick as
> >
> > { local $/ = undef;
> > $file = ; # slurp the whole file into $file
> > }
> >
> > which is more efficient than
> >
> >while() { $file .=
Paul <[EMAIL PROTECTED]> writes:
> BTW, this is another use of the same sort of trick as
>
> { local $/ = undef;
> $file = ; # slurp the whole file into $file
> }
>
> which is more efficient than
>
>while() { $file .= $_ }
>
> or
>
>$file = join '', ;
>
> Still, I have a co
List, I got this paragraph in recent correspondence with someone
off-list:
> I'm not so much discouraged as realize that I need a bit more time
> with Perl before I can understand most of what gets passed around in
> the list. I'll be back in a couple of months. From my short exposure,
> it seem
At 10:51 AM 5/31/01 -0700, Randal L. Schwartz wrote:
>There's a school of (mis-)thought that "a coderef is a closure". I
>don't know how that got started, but it's wrong. A closure is created
>only when lexical variables go out of scope. So a coderef without
>external references is *not* a clos
> "Jeff" == Jeff Pinyan <[EMAIL PROTECTED]> writes:
Jeff> I was scolded highly about that by Uri, back when my article[1] about
Jeff> closures. I, too, felt that foo() should be called a closure, but Uri
Jeff> seemed so convincing. If you're going to let me say that functions that
Jeff> ref
On May 31, Randal L. Schwartz said:
>> "Jeff" == Jeff Pinyan <[EMAIL PROTECTED]> writes:
>
>Jeff> A closure is an ANONYMOUS function (constructed via $x = sub {
>Jeff> ... }) that contains LEXICAL variables that have been defined in
>Jeff> a scope visible to the closure itself.
>
>leave out t
> "Randal" == Randal L Schwartz <[EMAIL PROTECTED]> writes:
> "Jeff" == Jeff Pinyan <[EMAIL PROTECTED]> writes:
Jeff> A closure is an ANONYMOUS function (constructed via $x = sub {
Jeff> ... }) that contains LEXICAL variables that have been defined in
Jeff> a scope visible to the closure
> "Jeff" == Jeff Pinyan <[EMAIL PROTECTED]> writes:
Jeff> A closure is an ANONYMOUS function (constructed via $x = sub {
Jeff> ... }) that contains LEXICAL variables that have been defined in
Jeff> a scope visible to the closure itself.
leave out the word ANONYMOUS there.
ANONYMOUS and CLOS
On May 31, Randal L. Schwartz said:
>Paul> Be careful with this, though -- if you call some other function
>Paul> from this scope, the value of $SIG{__WARN__} will still be the
>Paul> routine that increments $bad, but it won't be able to see the
>Paul> $bad we made with my()!
>
>Wrong. It'll sti
--- "Randal L. Schwartz" <[EMAIL PROTECTED]> wrote:
> > "Paul" == Paul <[EMAIL PROTECTED]> writes:
>
> Paul> This is lovely, and a great opportunity to show some new toys
> Paul> to beginners, as well as some well-placed caveats. With your
> Paul> indulgence, I'll try to break this down for
> "Paul" == Paul <[EMAIL PROTECTED]> writes:
Paul> This is lovely, and a great opportunity to show some new toys to
Paul> beginners, as well as some well-placed caveats. With your indulgence,
Paul> I'll try to break this down for the newbies. :)
Great!
Paul> Be careful with this, though --
--- "Randal L. Schwartz" <[EMAIL PROTECTED]> wrote:
>
> The most comprehensive test for a real number is to let Perl
> do it itself:
>
> sub is_number {
> my $bad = 0;
> local $SIG{__WARN__} = sub { $bad++ };
> local $^W = 1;
> my $guess = shift;
> $guess += 0;
> "Timothy" == Timothy Kimball <[EMAIL PROTECTED]> writes:
Timothy> Randal L. Schwartz wrote
Timothy> : For integers, you can narrow it down:
Timothy> :
Timothy> : sub is_integer {
Timothy> : my $bad = 0;
Timothy> : local $SIG{__WARN__} = sub { $bad++ };
Timothy> : loca
Randal L. Schwartz wrote
: For integers, you can narrow it down:
:
: sub is_integer {
: my $bad = 0;
: local $SIG{__WARN__} = sub { $bad++ };
: local $^W = 1;
: my $guess = shift;
: return $guess == int($guess) and not $bad;
: }
oops, precedence:
return $g
The most comprehensive test for a real number is to let Perl
do it itself:
sub is_number {
my $bad = 0;
local $SIG{__WARN__} = sub { $bad++ };
local $^W = 1;
my $guess = shift;
$guess += 0;
return not $bad;
}
If adding 0 didn't trigger the numeric war
Hi Mike,
You wrote:
>How do I test an input to see if it is a real number? I have a situation
>something like:
(slightly snipped)
>if (input equals a real number) {
>xx
>}
>else {
>
>}
Do you mean 'if it really is a number' or 'a real number' in the matematical
sense? If you
Good day;
try:::
if ($input =~ /\d+\.?\d+/){
xxx
}
The intent here is:
\d+ ##one or more digits
\.? ##followed by zero or one "." (there is a dot there)
\d+ ##followed by one or more digits.
I think this will work. Depending on how your reals will be input, you c
On May 30, [EMAIL PROTECTED] said:
>I'm new to the group and new to Perl and am very glad to have such a
>resource available. Hopefully someday I'll be on the giving end of the
>help list but for now I'm stumped. How do I test an input to see if it
>is a real number? I have a situation someth
--- [EMAIL PROTECTED] wrote:
> help list but for now I'm stumped. How do I test an input to see if
> it is a real number? I have a situation something like:
By "real number", exactly what do you mean?
Do you mean a decimal fraction without characters other than
0123456789.+- or do you want to i
On Wed, May 30, 2001 at 01:56:40PM -0700, [EMAIL PROTECTED] wrote:
> How do I test an input to see if it is a real number?
$ perldoc -q float
Found in /usr/local/lib/perl5/5.6.1/pod/perlfaq4.pod
How do I determine whether a scalar is a
number/whole/integer/float?
Assuming that y
Hi,
I'm new to the group and new to Perl and am very glad to have such a
resource available. Hopefully someday I'll be on the giving end of the
help list but for now I'm stumped. How do I test an input to see if it
is a real number? I have a situation something like:
$input = ;
chom
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