boolean - PHP - Get bool to echo false when false -

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for reason, following code doesn't print out anything:

$bool_val = (bool)false; echo $bool_val;

but following code prints out 1:

$bool_val = (bool)true; echo $bool_val;

is there better way print out 0 or false when $bool_val false adding if statement?

edit: changed second statement false true

echo $bool_val ? 'true' : 'false';

or if want output when it's false:

echo !$bool_val ? 'false' : '';

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