0 is False
"0"
is False
""
is False
undef
is False
all
else
is True
print
True;
# prints a blank
print
False;
# prints a blank
undef
# variables which have not been set have a value of undef
# using -w will catch
# some functions return undef on failure
Numeric:
$x
==
$y
True
if
$x
equals
$y
$x
>
$y
$X
<
$y
$x
>=
$y
$x
<=
$y
$x
!=
$y
True is
$x
is
not
equal to
$y
AlphaNumeric:
$x
eq
$y
$x
gt
$y
$x
lt
$y
$x
ge
$y
$x
le
$y
$x
ne
$y
Logical Operators:
and
/Or/
not
can
each
be written in two ways:
&&
and
# $a && $b $a and $b
||
or
# $a || $b $a or $b
!
not
# ! $b not $b
Special operators:
$c
++
# same as $c = $c + 1
$c
--
# same as $c = $c - 1
$a
+=
3
# same as $a = $a + 3
$y
*=
$x
# same as $y = $y * $x
$r%
=
67
# same as $r = $r % 67
qq
()
# quote-quote (double quotes)
q
()
# quote (single quote - no interpolation)
qw
()
# list with no interpolation (uses whitespace to separate list items)
$
#myarray # used to resize @myarray
