1 files changed, 75 insertions, 0 deletions

diff --git a/src/var.sh b/src/var.sh
new file mode 100644
index 0000000..d0c7df5
--- /dev/null
+++ b/src/var.sh
@@ -0,0 +1,75 @@
+die()
+{
+    if [ "$*" ]; then
+        printf 'Error: %s\n' "$*" >&2
+    else
+        echo 'Error: fatal error' >&2
+    fi
+    exit 1
+}
+
+nosex()
+{
+    case $- in
+        *x*) set +x; "$@"; set -x;;
+        *) "$@";;
+    esac
+}
+
+_nonempty()
+{
+    printf '[ "${%s}" ] || die \"mandatory parameter is empty: %s\";\n' "$1" "$1"
+}
+
+_mandatory()
+{
+    printf '[ $# -ge %d ] || die \"mandatory parameter is missing: %s\";\n' "$2" "$1"
+}
+
+_assign()
+{
+    printf 'local %s="${%d}";\n' "$1" "$2"
+}
+
+_args()
+{
+    local v i=1 check="$1" assign="$2"
+    shift
+    shift
+    for v; do
+        $assign "$v" "$i"
+        $check "$v" "$i"
+        i=$((i+1))
+    done
+}
+
+_ARGS()
+{
+    echo eval "$(_args _mandatory _assign "$@")"
+}
+
+_ARGS_NONEMPTY()
+{
+    echo eval "$(_args _nonempty _assign "$@")"
+}
+
+_ARGS_OPTIONAL()
+{
+    echo eval "$(_args : _assign "$@")"
+}
+
+_NONEMPTY()
+{
+    echo eval "$(_args _nonempty : "$@")"
+}
+
+ARGS()          { nosex _ARGS "$@"; }
+ARGS_NONEMPTY() { nosex _ARGS_NONEMPTY "$@"; }
+ARGS_OPTIONAL() { nosex _ARGS_OPTIONAL "$@"; }
+NONEMPTY()      { nosex _NONEMPTY "$@"; }
+
+ARGS_NE() { ARGS_NONEMPTY "$@"; }
+
+if [ "${0#-}" = bash ]; then
+    export -f die _nonempty _mandatory _args ARGS ARGS_NONEMPTY ARGS_OPTIONAL
+fi