[groff] 05/10: tmac/an-old.tmac (RE): Add style warnings.

[G. Branden Robinson]

gbranden pushed a commit to branch master
in repository groff.

commit 254b6aa0a2233e603144d515b35e79bd5c0497b3
Author: G. Branden Robinson <g.branden.robinson@gmail.com>
AuthorDate: Wed Jan 20 00:44:27 2021 +1100

    tmac/an-old.tmac (RE): Add style warnings.
    
    * tmac/an-old.tmac (RE): Style-warn if macro arguments are out of range
      or redundant.
    
    Fixes <https://savannah.gnu.org/bugs/?55320>.
    
    Tested with:
        .TH foo 1 "groff experiments" 2021-01-19
        .RE 1
        .RE 2
        .RE 0
        .RE
        .RS
        .RE
---
 ChangeLog        |  7 +++++++
 tmac/an-old.tmac | 15 +++++++++++++++
 2 files changed, 22 insertions(+)

diff --git a/ChangeLog b/ChangeLog
index 2d34cea..35153d4 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+2021-01-19  G. Branden Robinson <g.branden.robinson@gmail.com>
+
+       * tmac/an-old.tmac (RE): Style-warn if macro arguments are out
+       of range or redundant.
+
+       Fixes <https://savannah.gnu.org/bugs/?55320>.
+
 2021-01-15  G. Branden Robinson <g.branden.robinson@gmail.com>
 
        Improve style of troffrc{,-end} files.  Follow established
diff --git a/tmac/an-old.tmac b/tmac/an-old.tmac
index b7781ec..ba1ad64 100644
--- a/tmac/an-old.tmac
+++ b/tmac/an-old.tmac
@@ -579,6 +579,21 @@
 ..
 .
 .de1 RE
+.  ie \\n[.$] .nr an-RE-requested-level \\$1
+.  el         .nr an-RE-requested-level (\\n[an-level] - 1)
+.  ie \\n[.$] \{\
+.    if (\\n[an-RE-requested-level] = \\n[an-level]) \
+.      ds an-RE-problem redundant; already at level \\n[an-level]\"
+.    if (\\n[an-RE-requested-level] > \\n[an-level]) \
+.      ds an-RE-problem too large\"
+.    if (\\n[an-RE-requested-level] < 1) \
+.      ds an-RE-problem too small\"
+.    if d an-RE-problem \
+.      an-style-warn argument """\\$1""" to .\\$0 \\*[an-RE-problem]
+.    rm an-RE-problem
+.  \}
+.  el .if !(\\n[an-RE-requested-level]) .an-style-warn unbalanced .\\$0
+.  rr an-RE-requested-level
 .  ie \\n[.$] .nr an-level ((;\\$1) <? \\n[an-level])
 .  el         .nr an-level -1
 .  nr an-level (1 >? \\n[an-level])