Selector operator, multi-operand, added

operand-selector-case.go

@@ -0,0 +1,37 @@
+// Copyright (c) 2024 Celestino Amoroso (celestino.amoroso@gmail.com).
+// All rights reserved.
+
+// operand-selector-case.go
+package expr
+
+import "fmt"
+
+// -------- selector case term
+
+type selectorCase struct {
+	filterList *term
+	caseExpr   Expr
+}
+
+func newSelectorCaseTerm(row, col int, filterList *term, caseExpr Expr) *term {
+	tk := NewValueToken(row, col, SymSelectorCase, "", &selectorCase{filterList: filterList, caseExpr: caseExpr})
+	return &term{
+		tk:       *tk,
+		class:    classVar,
+		kind:     kindUnknown,
+		parent:   nil,
+		children: nil,
+		position: posLeaf,
+		priority: priValue,
+		evalFunc: evalSelectorCase,
+	}
+}
+
+// -------- eval selector case
+func evalSelectorCase(ctx exprContext, self *term) (v any, err error) {
+	var ok bool
+	if v, ok = self.value().(*selectorCase); !ok {
+		err = fmt.Errorf("selector-case expected, got %T", self.value())
+	}
+	return
+}