// operand-func.go
package expr

// -------- function term
func newFuncTerm(tk *Token, args []*term) *term {
	return &term{
		tk:       *tk,
		class:    classVar,
		kind:     kindUnknown,
		parent:   nil,
		children: args,
		position: posLeaf,
		priority: priValue,
		evalFunc: evalFunc,
	}
}

// -------- eval func
func evalFunc(ctx exprContext, self *term) (v any, err error) {
	name, _ := self.tk.Value.(string)
	params := make([]any, len(self.children))
	for i, tree := range self.children {
		var param any
		if param, err = tree.compute(ctx); err != nil {
			break
		}
		params[i] = param
	}
	if err == nil {
		v, err = ctx.Call(name, params)
	}
	return
}