draft

Local variables

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]);
Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s