curly braces variables
I have this: 

    echo 'm=>'.$fin_type_2; // echoes 'test text';

Now, if I do the following, I get nothing, whereas I was expecting the same result as above. What I am doing wrong here ?

    $z=2;
    echo 'm=>'.$fin_type_{$z}; // echoes nothing but m=>

Help appreciated. 
Many thanks.
curly braces variables
===

I have this: 

    echo 'm=>'.$fin_type_2; // echoes 'test text';

Now, if I do the following, I get nothing, whereas I was expecting the same result as above. What I am doing wrong here ?

    $z=2;
    echo 'm=>'.$fin_type_{$z}; // echoes nothing but m=>

Help appreciated. 
Many thanks.