[PHP truthy falsey] #php

phptruthy.txt

$my_var = false;
if ( isset( $my_var ) ) {
  echo "It's set!";
} else {
  echo "It's not set.";
}

The empty() function checks if the variable is an empty string, 0, NULL, or false.

$my_var = false;
if ( empty( $my_var ) ) {
  echo "It's empty!";
} else {
  echo "It's not empty.";
}
It will return false if the variable has a non-empty and non-zero value.