The parser expects a bareword or a simple scalar for the method name. The idiomatic approach is to use a scalar dereference operation when dealing with more syntactically complex scalars e.g 
print $image->${ \$ext{JPEG} };

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HTH

_________
broquaint

In reply to Re: subroutine referencing by broquaint
in thread subroutine referencing by imcsk8

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