sub isNumber {
local( $_ )= @_;
my( $ok, $val, $base );
if( s/h$//i && s/^/0x/
|| m/^0x/ ) {
$ok= m/^0x[\da-f]+$/i;
$val= hex($_);
$base= 16;
} elsif( s/o$//i ) {
$ok= m/^[0-7]+$/;
$val= oct($_);
$base= 8;
} else {
my $warn;
local( $SIG{__WARN__} )= sub {
$warn= $_[0];
};
local( $^W )= 1;
$val= 0 + $_;
$ok= ! $warn;
$base= 10;
}
$_[1]= $val;
$_[2]= $base;
return $ok;
}
my $num= <STDIN>;
my $val;
if( isNumber( $num, $val, $base ) ) {
print "Your number's value is $val in base $base.\n";
} else {
print "Your number is invalid but might be close to $val in base $
+base.\n";
}
Note that I didn't treat a leading zero as octal and I'm a bit inconsistant with how much whitespace I'll ignore.
Updated: To return the base.
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tye
(but my friends call me "Tye")
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