php interactive shell doesn't have any output?

Question

bash-3.2$ php -a Interactive shell

php > $a = null || "hi" php > echo $a php > $b = "hi" php > echo $b 

As you can see here, nothing is being echoed.
Why is that? I'm using Mac OS X lion. =\ (fresh install)

Answer 1

You've forgoten to put semicolons at the end of each line. Should be:

php > $a = null || "hi"; php > echo $a; php > $b = "hi"; php > echo $b; 

Answer 2

I had the same problem:

php > echo $undefined_var 

but after put ; in other line

php > ; 

Result:

 Undefined variable: "undefined" in php shell code on line 2 

So, is possible make this:

php > echo 123456 php > ; php > echo 123456;