use Compiler::Errors 'file.out';    # will append
use Compiler::Errors '>file.out';   # will overwrite
use Compiler::Errors '>>file.out';  # will append
use Compiler::Errors '| program';   # will pipe
use Compiler::Errors '>&=1';        # dup to fd
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package Compiler::Errors;

sub import {
  shift;  # caller
  my $file = @_ ? shift : "compiler.err";

  # default to appending to the file
  $file = ">> $file" if $file !~ /^[>|]/;

  open __SAVEERR, ">&STDERR";  # copy STDERR
  open STDERR, $file;          # redirect STDERR
}

INIT {
  open STDERR, ">&__SAVEERR";  # restore STDERR
  close __SAVEERR;
}

1;
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