Re^3: Replacing environment variables

[holli]

while (<DATA>)
{
    # match any dollar followed by a number
    # of non whitespaces (unicode safe)
    # and replace it by then corresponding
    # environment variable
    
    if ( s/\$(\P{IsSpace}+)/$ENV{$1}/ )
    {
        $undefinedVars++ 
            unless $ENV{$1};
    }
    
    print;
}

if ( $undefinedVars > 0) 
{ 
    print "\n\nERROR: There were $undefinedVars undefined variables!\n
+"; 
}

__DATA__
bigcompany.product.part.path=$PATH
bigcompany.product.part.widgit=$WIDGIT
bigcompany.product.part.battery=$BATTERY
bigcompany.product.part.frobnicator=$FROBNICATOR

[loris]

Thanks for the nice concise solution, holli. Looking at it, I realise that I have missed out the case where the environment variable represents a directory and may be followed by a subdirectory (see updated OP). Thus the regexp would have to be a little different.

loris