3.2. Accessing data files from package code

The placement on the target system of files listed in the data-files field varies between systems, and in some cases one can even move packages around after installation (see Section 4.1.2.3, “Prefix-independence”). To enable packages to find these files in a portable way, Cabal generates a module called Paths_pkgname (with any hyphens in pkgname replaced by underscores) during building, so that it may be imported by modules of the package. This module defines a function

getDataFileName :: FilePath -> IO FilePath

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