Having worked on a lot of code that did such things, I found that I had much fewer regrets with the almost subtly different: 

my $msg_body_1 = join '',
   "line 1\n",
   "line 2\n",
   "line3a  \t  \line3b\n",
   "line4",
   "\n\n",
;

[download]

'.' binds tighter than a lot of things that are pretty common to include in a list of things to be joined together. The "no trailing '.' allowed" problem (an endless source of pain for me outside of Perl but in the form of "no trailing comma allowed") goes away when using comma.

- tye        

In reply to Re^4: Formatting Strings Without Interpolating Whitespace (join) by tye
in thread Formatting Strings Without Interpolating Whitespace by BJ_Covert_Action

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