|
Result of a subroutine is always the last thing evaluated. This subroutine returns the maximum of two input parameters. An example of its use follows.
sub maximum
{
if ($_[0] > $_[1])
{
$_[0];
}
else
{
$_[1];
}
}
$biggest = &maximum(37, 24); # Now $biggest is 37
The &printfirsttwo subroutine above also returns a value, in this case 1. This is because the last thing that subroutine did was a print statement and the result of a successful print statement is always 1.
Local variables
Greenwich Village movers
The @_ variable is local to the current subroutine, and so of course are $_[0], $_[1], $_[2], and so on. Other variables can be made local too, and this is useful if we want to start altering the input parameters. The following subroutine tests to see if one string is inside another, spaces not withstanding. An example follows.
sub inside
{
local($a, $b); # Make local variables
($a, $b) = ($_[0], $_[1]); # Assign values
$a =~ s/ //g; # Strip spaces from
$b =~ s/ //g; # local variables
($a =~ /$b/ || $b =~ /$a/); # Is $b inside $a
# or $a inside $b?
}
&inside("lemon", "dole money"); # true
In fact, it can even be tidied up by replacing the first two lines with
local($a, $b) = ($_[0], $_[1]);
| 
