When $v contains "a", you want to execute 
$a = $a * 2

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Which you means you have to build that string and pass it to the parser (eval EXPR). That can be done using the string literal 

"\$$v = \$$v * 2"

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So you want 

eval "\$$v = \$$v * 2; 1" or die $@;

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In reply to Re: eval & variable names? by ikegami
in thread eval & variable names? by Anonymous Monk

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