I have this function in one of my perl applications, what allows a user to use a regex to parse out some of the data, and it works fine 
$data = "this is a test"
$expression_text = "(.*)es"

$data =~ $expression_text
$result = $1 which is 'this is a t';

[download]
but if the expression is really a command, replace for example, then it fails.. 
$data = "this is a test"
$expression_text = "s/es/dd/g"
$data =~ $expression_text

[download]

a particular example is a file name string which was put into a file with single quotes, and on the commandline it needs to be double quotes..

'somefile.dat' = "somefile.dat", s// would do that fine..

but I can't seem to understand the nuance of getting perl to execute it properly.. using re debug,
it shows that the text in the right side variable is treated as the ENTIRE string to match against.
re eval doesn't help.
evl (var = var) doesn't do it.

oh sage ones, show me the light..

In reply to using just variables in a regular exression by sdetweil

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