In my response to Timothy Luoma's question yesterday I used an incorrect
condition to check for something that looked like a header at the beginning
of the body.
The recipe should read as follows:
:0Bfw # brackets enclose caret, space, tab
* ^^($)*[^ ]+:
| sed -e '/^$/,$!b' -e '/./,$!d'
The condition I originally gave had two errors: it assumed that there would
be only one spuriously inserted blank line above the rest of the headers,
and since I carelessly left out the plus sign it required the next header
line to have a one-character name.
It should be noted that the corrected condition can also be written this way:
* ^^(^)*[^ ]+:
where the four carets have three different meanings, none of them denoting a
literal caret in the text. Fun stuff, huh?