[groff] 06/14: [tbl]: Supply (empty) fallback `T&` definition.

[G. Branden Robinson]

gbranden pushed a commit to branch master
in repository groff.

commit 91cee73b19b46e759abc92037940b7a5df0daa18
Author: G. Branden Robinson <g.branden.robinson@gmail.com>
AuthorDate: Sun Oct 31 19:56:45 2021 +1100

    [tbl]: Supply (empty) fallback `T&` definition.
    
    * src/preproc/tbl/main.cpp (main): Emit groff code to define macro `T&`
      as empty if it is not already defined.  (All of our full-service macro
      packages [except mdoc(7)] already do this, so there's no change in
      semantics; mom(7) even defines it as an empty _string_.)
---
 ChangeLog                | 8 ++++++++
 src/preproc/tbl/main.cpp | 1 +
 2 files changed, 9 insertions(+)

diff --git a/ChangeLog b/ChangeLog
index 32da712..ae58232 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,13 @@
 2021-10-31  G. Branden Robinson <g.branden.robinson@gmail.com>
 
+       * src/preproc/tbl/main.cpp (main): Emit groff code to define
+       macro `T&` as empty if it is not already defined.  (All of our
+       full-service macro packages [except mdoc(7)] already do this, so
+       there's no change in semantics; mom(7) even defines it as an
+       empty _string_.)
+
+2021-10-31  G. Branden Robinson <g.branden.robinson@gmail.com>
+
        * src/roff/groff/tests/string_case_xform_requests.sh: Migrate
        test to POSIX shell, dropping use of process substitution (a
        Bashism).  Also rewrite to stop using a here document within a
diff --git a/src/preproc/tbl/main.cpp b/src/preproc/tbl/main.cpp
index 8cb19e8..2c2d879 100644
--- a/src/preproc/tbl/main.cpp
+++ b/src/preproc/tbl/main.cpp
@@ -1595,6 +1595,7 @@ int main(int argc, char **argv)
     }
   printf(".if !\\n(.g .ab GNU tbl requires groff extensions; aborting\n"
         ".do if !dTS .ds TS\n"
+        ".do if !dT& .ds T&\n"
         ".do if !dTE .ds TE\n");
   if (argc > optind) {
     for (int i = optind; i < argc; i++)