I am trying (for example) to identify the subset of directories (in a list of directories) that contain a file beginning with the letter 'f'.
I am using the following sample code to test: 
perl -e 'use Data::Dumper;  print Dumper  grep(glob("$_/f*"),("dir1", 
+"dir2", "dir3") )'

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The idea being that the glob (evaluated) in scalar context, returns true if there is a file of form dirN/f*

However, somehow it is seemingly not being evaluated in scalar context to the extent that if dir1 contains N files beginning with 'f' then the first N directories are returned by grep even if none of the others contain a file beginning with 'f'. It is as if glob is not being evaluated in scalar context. Note even if I force glob to scalar using (scalar glob("$_/f*")), it still fails this way.

Any clue what is going wrong?
Any suggestions for alternative approaches?

In reply to Using grep and glob to find directories containing file by Anonymous Monk

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