support Is combinator for constrains

fogfish · Nov 30, 2020 · 6467d59 · 6467d59
1 parent 580b7c3
commit 6467d59
Showing 1 changed file with 12 additions and 0 deletions.
diff --git a/constrain.go b/constrain.go
@@ -163,6 +163,18 @@ func (e ElemIs) Ge(val interface{}) Config {
 	return e.compare(">=", val)
 }
 
+/*
+
+Is matches either Eq or NotExists if value is not defined
+*/
+func (e ElemIs) Is(val string) Config {
+	if val == "_" {
+		return e.NotExists()
+	}
+
+	return e.Eq(val)
+}
+
 func (e ElemIs) compare(fn string, val interface{}) Config {
 	return func(
 		conditionExpression **string,