Is it anywhere documented what syntax is allowed in the index expression of a hash or array element interpolated into a string? I haven't been able to find any explicit documentation, but from playing around it appears that many (but not all) expressions which are allowed outside of interpolation are also allowed in an interpolation. For example,
   qq< $h{  fn("{") =~ /c/ } >
is allowed but
   qq< $h->{  fn("{") =~ /c/ } >
is not.

In reply to Syntax allowed in interpolated hash/array indexes by jrw

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