Already one year old message, but nevertheless... It is better to use a method, because the context might not have that variable `$c` defined. It is NOT automatically a global variable, but it might be context dependent.
Second issue of using a variable is that it might be overwritten (using something as ubiquitous as a letter `c` for a (pseudo) global variable is already giving me the creeps), but a method will never be overwritten in PHP.
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