research/ref.sh: New file

1 files changed, 66 insertions, 0 deletions

diff --git a/research/ref.sh b/research/ref.sh
new file mode 100644
index 0000000..88f1d31
--- /dev/null
+++ b/research/ref.sh
@@ -0,0 +1,66 @@
+foo()
+{
+	local var=1
+
+	bar var
+}
+
+bar(string ref)
+{
+	local var=2
+
+	eval "${ref}=3"
+}
+
+
+
+foo()
+{
+	local var=1
+
+	bar &var
+}
+
+bar(string ref)
+{
+	local var=2
+
+	!ref=3
+}
+
+
+
+__ref()
+{
+	__var=${1}
+
+	case " ${__fn_vars} " in *" ${__var} "*)
+		printf '__fn_vars_%d_%s' ${__sp} "${__var}"
+		return 0
+	;; esac
+	eval "__val=\${__${__prev_tu}_static_vars}"
+	case " ${__val} " in *" ${__var} "*)
+		printf '__fn_vars_%d_%s' ${__sp} "${__var}"
+		return 0
+	;; esac
+}
+
+__derefset()
+{
+	__var=${1}
+	
+	case "${__var}" in
+		*[!A-Za-z0-9_]*)
+			printf 'Error: Invalid reference variable\n' >&2
+			exit 1
+			;;
+		'__fn_vars_'[A-Za-z_]*)
+			;;
+		*)
+			printf 'Error: Invalid reference variable\n' >&2
+			exit 1
+			;;
+	esac
+
+	eval "printf '%s' \${${__var#__fn_vars_}}"
+}