=head2 Function Templates
-As explained above, a closure is an anonymous function with access to the
-lexical variables visible when that function was compiled. It retains
-access to those variables even though it doesn't get run until later,
-such as in a signal handler or a Tk callback.
+As explained above, an anonymous function with access to the lexical
+variables visible when that function was compiled, creates a closure. It
+retains access to those variables even though it doesn't get run until
+later, such as in a signal handler or a Tk callback.
Using a closure as a function template allows us to generate many functions
that act similarly. Suppose you wanted functions named after the colors
Access to lexicals that change over type--like those in the C<for> loop
above--only works with closures, not general subroutines. In the general
case, then, named subroutines do not nest properly, although anonymous
-ones do. If you are accustomed to using nested subroutines in other
-programming languages with their own private variables, you'll have to
-work at it a bit in Perl. The intuitive coding of this type of thing
-incurs mysterious warnings about ``will not stay shared''. For example,
-this won't work:
+ones do. Thus is because named subroutines are created (and capture any
+outer lexicals) only once at compile time, whereas anonymous subroutines
+get to capture each time you execute the 'sub' operator. If you are
+accustomed to using nested subroutines in other programming languages with
+their own private variables, you'll have to work at it a bit in Perl. The
+intuitive coding of this type of thing incurs mysterious warnings about
+``will not stay shared''. For example, this won't work:
sub outer {
my $x = $_[0] + 35;
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