I will usually access external functions in one of two styles:

  use Your::Module ();
  printf "timestamp: %s\n", Your::Module::timestamp(time);

  use Your::Module qw/ timestamp /;
  printf "timestamp: %s\n", timestamp(time);
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I use these styles because I don't like action at a distance. When looking at a function call in my code, I want it to be clear either from the line of code itself or from a declaration in the same source file where I'd find the function being called.

Further, when allowing an unspecified import, there is always the danger that the name of an exported function clashes with a local name. I don't want to have to check for that when I use a module, and I certainly don't want to have to check for it throughout my code when I upgrade a module.

Most of the modules I write myself are OO, so this question doesn't arise. For the few that include only functions, I don't use Exporter: I expect the caller to fully qualify calls, or set up their own alias - which is as simple as:

  *timestamp = \&Your::Module::timestamp;
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Hugo