bin/: Use explicit "--" separator for assert-arg usages

In order to prevent legitimate cases to fail as errors, such as:

  NUM='-10'
  eval "$(assert-arg "$NUM" '-n NUM')"

To prevent assert-arg(1) from treating "-10" as the options "-1 and -0,
they need to be put after the "--" separator.

This way, all usages of assert-arg(1) that had its first argument as a
variable were adapted, and the usage and examples of assert-arg itself
were updated to encourage this best practice.

1 files changed, 1 insertions, 1 deletions

diff --git a/bin/rfc b/bin/rfc
index 9c71ebc..0860f45 100755
--- a/bin/rfc
+++ b/bin/rfc
@@ -133,7 +133,7 @@ if [ "${UPDATE:-}" = true ]; then
 	exit
 fi
 
-eval "$(assert-arg "$RFC_NUMBER" 'RFC_NUMBER')"
+eval "$(assert-arg -- "$RFC_NUMBER" 'RFC_NUMBER')"
 
 if [ ! -e "$F" ]; then
 	printf 'Given RFC_NUMBER "%s" does not exist at:\n%s\n' \