From 0e3f0b740ea18224c3b2c07114be601dd8be97bb Mon Sep 17 00:00:00 2001 From: Ingo Schwarze Date: Sat, 15 Dec 2018 19:30:25 +0000 Subject: Several improvements to escape sequence handling. * Add the missing special character \_ (underscore). * Partial implementations of \a (leader character) and \E (uninterpreted escape character). * Parse and ignore \r (reverse line feed). * Add a WARNING message about undefined escape sequences. * Add an UNSUPP message about unsupported escape sequences. * Mark \! and \? (transparent throughput) and \O (suppress output) as unsupported. * Treat the various variants of zero-width spaces as one-byte escape sequences rather than as special characters, to avoid defining bogus forms with square brackets. * For special characters with one-byte names, do not define bogus forms with square brackets, except for \[-], which is valid. * In the form with square brackets, undefined special characters do not fall back to printing the name verbatim, not even for one-byte names. * Starting a special character name with a blank is an error. * Undefined escape sequences never abort formatting of the input string, not even in HTML output mode. * Document the newly handled escapes, and a few that were missing. * Regression tests for most of the above. --- mandoc.1 | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) (limited to 'mandoc.1') diff --git a/mandoc.1 b/mandoc.1 index 91b3003f..7aeaa0b6 100644 --- a/mandoc.1 +++ b/mandoc.1 @@ -1676,7 +1676,8 @@ Start it on a new input line to help formatters produce correct spacing. .It Sy "invalid escape sequence" .Pq roff An escape sequence has an invalid opening argument delimiter, lacks the -closing argument delimiter, or the argument has too few characters. +closing argument delimiter, the argument is of an invalid form, or it is +a character escape sequence with an invalid name. If the argument is incomplete, .Ic \e* and @@ -1689,6 +1690,12 @@ and .Ic \ew to the length of the incomplete argument. All other invalid escape sequences are ignored. +.It Sy "undefined escape, printing literally" +.Pq roff +In an escape sequence, the first character +right after the leading backslash is invalid. +That character is printed literally, +which is equivalent to ignoring the backslash. .It Sy "undefined string, using \(dq\(dq" .Pq roff If a string is used without being defined before, @@ -2154,6 +2161,13 @@ implementations but not by .Nm was found in an input file. It is replaced by a question mark. +.It Sy "unsupported escape sequence" +.Pq roff +An input file contains an escape sequence supported by GNU troff +or Heirloom troff but not by +.Nm , +and it is likely that this will cause information loss +or considerable misformatting. .It Sy "unsupported roff request" .Pq roff An input file contains a -- cgit