Description:
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Scenario:
a database driven CMS, article contents are retrieved from the database and stored into a string variable.
The output is usually shown using "echo".
If the article contains some php code it is not executed, but printed on screen.
The alternative is to write the entire article as php code, retrieve it and then process it using "eval".
An even more complicated variant is to create a temporary file, containing both xHTML and php code, and then process it using "include".

It would be extremely useful to have a variant of the "include" function, that can take as input not just a file path, but a string variable, containing both xHTML and php code.