[groff] 14/35: tmac/an-ext.tmac: Slightly refactor hyphenation.

[G. Branden Robinson]

gbranden pushed a commit to branch master
in repository groff.

commit 096c2f056746f4fd0de3ed7e060c58e5e8d6afb5
Author: G. Branden Robinson <g.branden.robinson@gmail.com>
AuthorDate: Wed Feb 16 16:03:59 2022 +1100

    tmac/an-ext.tmac: Slightly refactor hyphenation.
    
    * tmac/an-ext.tmac: Slightly refactor.  Stop using groff's `HY` register
      to restore the hyphenation mode, since I plan to change its semantics
      to a Boolean value (see Savannah #61734).  Introduce new register `mJ`
      to store "1" (if not groff) and the current hyphenation mode
      otherwise.  Explain why in a comment.
    
      (YS, UE, ME, MR): Restore hyphenation mode using `mJ` insted of `HY`.
---
 ChangeLog        | 10 ++++++++++
 tmac/an-ext.tmac | 18 ++++++++++++------
 2 files changed, 22 insertions(+), 6 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 4474b5a7..eee25d51 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,13 @@
+2022-02-16  G. Branden Robinson <g.branden.robinson@gmail.com>
+
+       * tmac/an-ext.tmac: Slightly refactor.  Stop using groff's `HY`
+       register to restore the hyphenation mode, since I plan to change
+       its semantics to a Boolean value (see Savannah #61734).
+       Introduce new register `mJ` to store "1" (if not groff) and the
+       current hyphenation mode otherwise.  Explain why in a comment.
+       (YS, UE, ME, MR): Restore hyphenation mode using `mJ` insted of
+       `HY`.
+
 2022-02-16  G. Branden Robinson <g.branden.robinson@gmail.com>
 
        * tmac/an-ext.tmac: Trivially refactor.  Use a better idiom
diff --git a/tmac/an-ext.tmac b/tmac/an-ext.tmac
index 78af9b4d..15011e53 100644
--- a/tmac/an-ext.tmac
+++ b/tmac/an-ext.tmac
@@ -27,6 +27,14 @@
 .if \n(mX>1 \
 .  nx
 .
+.\" In AT&T troff, there was no register exposing the hyphenation mode,
+.\" and no way to save and restore it.  Set this to a reasonable value
+.\" for your implementation and preference.
+.ie !\n(.g \
+.  nr mJ 1
+.el \
+.  do nr mJ \n[.hy]
+.
 .\" Check if we're using grohtml or grotty, and therefore support URIs.
 .nr mH 0
 .nr mY 0
@@ -62,8 +70,6 @@
 .el \{\
 .  ds mL <\"
 .  ds mR >\"
-.  \" groff's man macros control hyphenation with this register.
-.  nr HY 1
 .\}
 .
 .nr mS 0
@@ -93,7 +99,7 @@
 .de YS
 .  in \\n(mIu
 .  ad \\n(mA
-.  hy \\n(HY
+.  hy \\n(mJ
 .  nr mS 0
 ..
 .
@@ -148,7 +154,7 @@
 .    do shift
 .    ie \n(.g .if \n(.$ \&\\$*\"
 .    el .if \n(.$>1 \\$2 \\$3 \\$4 \\$5 \\$6 \\$7 \\$8 \\$9\"
-.    hy \\n(HY
+.    hy \\n(mJ
 .  \}
 . rr mD
 ..
@@ -204,7 +210,7 @@
 .    do shift
 .    ie \n(.g .if \n(.$ \&\\$*\"
 .    el .if \n(.$>1 \\$2 \\$3 \\$4 \\$5 \\$6 \\$7 \\$8 \\$9\"
-.    hy \\n(HY
+.    hy \\n(mJ
 .  \}
 . rr mD
 ..
@@ -219,7 +225,7 @@
 .    I \\$1
 .  el \
 .    IR \\$1 (\\$2)\\$3
-.  hy \\n(HY
+.  hy \\n(mJ
 ..
 .
 .