logical operators

logical operators

Perl

sub return_true {
    print "return_true";
    return 1;
}

sub return_false {
    print "return_false";
    return 0;
}

print "&&  ";
if (return_false() && return_true()) {
}
print "\n";

print "and ";
if (return_false() and return_true()) {
}
print "\n";

print "||  ";
if (return_true() || return_false()) {
}
print "\n";

print "or  ";
if (return_true() or return_false()) {
}
print "\n";

print "!   ";
if (!return_false()) {
    print "\n";
}

print "not ";
if (not return_false()) {
    print "\n";
}

print "? : ";
return_true() ? print " true" : print " false"

L:\>perl lesson012.pl
&&  return_false
and return_false
||  return_true
or  return_true
!   return_false
not return_false
? : return_true true

Ruby

def return_true
    print "return_true"
    return true
end

def return_false
    print "return_false"
    return false
end

print "&&  "
if return_false && return_true
end
puts

print "and "
if return_false and return_true
end
puts

print "||  "
if return_true || return_false
end
puts

print "or  "
if return_true or return_false
end
puts

print "!   "
if !return_false
    puts
end

print "not "
if not return_false
    puts
end

print "? : "
return_true ? print(" true") : print(" false")

L:\>ruby lesson012.rb
&&  return_false
and return_false
||  return_true
or  return_true
!   return_false
not return_false
? : return_true true

PHP

<?php
function return_true() {
    print "return_true";
    return true;
}

function return_false() {
    print "return_false";
    return false;
}

print "&&  ";
if (return_false() && return_true())
    ;
print "\n";

print "and ";
if (return_false() and return_true())
    ;
print "\n";

print "||  ";
if (return_true() || return_false())
    ;
print "\n";

print "or  ";
if (return_true() or return_false())
    ;
print "\n";

print "!   ";
if (!return_false())
    print "\n";

print "xor ";
if (return_true() xor return_false())
    print "\n";

print "? : ";
return_true() ? print " true" : print " false"
?>

L:\>php lesson012.php
&&  return_false
and return_false
||  return_true
or  return_true
!   return_false
xor return_truereturn_false
? : return_true true

Python

import sys

def return_true():
    print "return_true",
    return True

def return_false():
    print "return_false",
    return False

print "and ",
if return_false() and return_true():
    pass
print

print "or  ",
if return_true() or return_false():
    pass
print

print "not ",
if not return_false():
    print

print "? : ",
sys.stdout.write(" true") if return_true() else sys.stdout.write(" false")

L:\>python lesson012.py
and  return_false
or   return_true
not  return_false
? :  return_true true