Warnings: Warn for confusing single-char $ expansions

Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>

diff --git a/generate b/generate
index eb99456144302fe5e20ef5b09f22dade5702dbef..c9ade62c3299518c72847b8f8528ffb4764df199 100755 (executable)
--- a/generate
+++ b/generate
@@ -288,6 +288,10 @@ sub process_input_mk ($$$$) {
            } elsif ($2 eq '$') {
                od $2;
                if (s{^\$}{}) { od $&; }
+               elsif (m{^[a-zA-Z]\w}) {
+                   wrn
+                   'possibly confusing unbracketed single-char $-expansion';
+               }
                elsif (m{^\(($esc)?([^()\$]+)\)} ||
                       m{^\{($esc)?([^{}\$]+)\}}) {
                    $note_varref->($2,!!$1);