[groff] 01/12: [me]: Accept empty first argument to `2c`.

[G. Branden Robinson]

gbranden pushed a commit to branch master
in repository groff.

commit 01cf10eb566514d70741f548efd5b5545efc1fa4
Author: G. Branden Robinson <g.branden.robinson@gmail.com>
AuthorDate: Wed Dec 15 10:44:10 2021 +1100

    [me]: Accept empty first argument to `2c`.
    
    * tmac/e.tmac (2c): Accept an empty first argument, permitting the
      number of columns to be specified but preserving the default column
      separation.
    
    Fixes <https://savannah.gnu.org/bugs/?61671>.
---
 ChangeLog   | 8 ++++++++
 tmac/e.tmac | 9 +++++----
 2 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 90c7559..fe8927d 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,11 @@
+2021-12-15  G. Branden Robinson <g.branden.robinson@gmail.com>
+
+       * tmac/e.tmac (2c): Accept an empty first argument, permitting
+       the number of columns to be specified but preserving the default
+       column separation.
+
+       Fixes <https://savannah.gnu.org/bugs/?61671>.
+
 2021-12-12  G. Branden Robinson <g.branden.robinson@gmail.com>
 
        * tmac/e.tmac (initialization): Initialize `$C` hook, preventing
diff --git a/tmac/e.tmac b/tmac/e.tmac
index 94be11c..39d8c1b 100644
--- a/tmac/e.tmac
+++ b/tmac/e.tmac
@@ -951,13 +951,14 @@
 .do check_page_length
 .br
 .if \\n($m>1 \
-.      1c\"                    \" revert to 1c if already 2c
+.      1c\"                            \" revert to 1c if already 2c
 .nr $c 1
 .nr $m 2
 .if \\n(.$>1 \
-.      nr $m \\$2
-.if \\n(.$>0 \
-.      nr $s \\$1n             \" param 1: column separation
+.      nr $m \\$2                      \" param 2: column quantity
+.      if \\n(.$>0 \
+.              if !'\\$1'' \
+.                      nr $s \\$1n     \" param 1: column separation
 .nr $l (\\n(.l-((\\n($m-1)*\\n($s))/\\n($m
 .xl \\n($lu
 .mk _k