#!./perl -w
+# tests state variables
BEGIN {
chdir 't' if -d 't';
}
use strict;
+use feature "state";
-plan tests => 19;
+plan tests => 32;
ok( ! defined state $uninit, q(state vars are undef by default) );
+# basic functionality
+
sub stateful {
state $x;
state $y = 1;
is( $y, 3, 'incremented state var' );
is( $z, 2, 'reinitialized lexical' );
+# in a nested block
+
sub nesting {
state $foo = 10;
my $t;
is( $x, 12, 'outer state var' );
is( $y, 14, 'inner state var' );
+# in a closure
+
sub generator {
my $outer;
# we use $outer to generate a closure
is( $f2->(), 1, 'generator 2' );
is( $f1->(), 3, 'generator 1 again' );
is( $f2->(), 2, 'generator 2 once more' );
+
+# with ties
+{
+ package countfetches;
+ our $fetchcount = 0;
+ sub TIESCALAR {bless {}};
+ sub FETCH { ++$fetchcount; 18 };
+ tie my $y, "countfetches";
+ sub foo { state $x = $y; $x++ }
+ ::is( foo(), 18, "initialisation with tied variable" );
+ ::is( foo(), 19, "increments correctly" );
+ ::is( foo(), 20, "increments correctly, twice" );
+ ::is( $fetchcount, 1, "fetch only called once" );
+}
+
+# state variables are shared among closures
+
+sub gen_cashier {
+ my $amount = shift;
+ state $cash_in_store = 0;
+ return {
+ add => sub { $cash_in_store += $amount },
+ del => sub { $cash_in_store -= $amount },
+ bal => sub { $cash_in_store },
+ };
+}
+
+gen_cashier(59)->{add}->();
+gen_cashier(17)->{del}->();
+is( gen_cashier()->{bal}->(), 42, '$42 in my drawer' );
+
+# stateless assignment to a state variable
+
+sub stateless {
+ (state $reinitme, my $foo) = (42, 'bar');
+ ++$reinitme;
+}
+is( stateless(), 43, 'stateless function, first time' );
+is( stateless(), 43, 'stateless function, second time' );
+
+# array state vars
+
+sub stateful_array {
+ state @x;
+ push @x, 'x';
+ return $#x;
+}
+
+my $xsize = stateful_array();
+is( $xsize, 0, 'uninitialized state array' );
+
+$xsize = stateful_array();
+is( $xsize, 1, 'uninitialized state array after one iteration' );
+
+# hash state vars
+
+sub stateful_hash {
+ state %hx;
+ return $hx{foo}++;
+}
+
+my $xhval = stateful_hash();
+is( $xhval, 0, 'uninitialized state hash' );
+
+$xhval = stateful_hash();
+is( $xhval, 1, 'uninitialized state hash after one iteration' );
+
+# state declaration with a list
+
+sub statelist {
+ # note that this should be a state assignment, while (state $lager, state $stout) shouldn't
+ state($lager, $stout) = (11, 22);
+ $lager++;
+ $stout++;
+ "$lager/$stout";
+}
+
+my $ls = statelist();
+is($ls, "12/23", 'list assignment to state scalars');
+$ls = statelist();
+is($ls, "13/24", 'list assignment to state scalars');