34 lines
564 B
Go
34 lines
564 B
Go
package node
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// Nullable node
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type Nullable struct {
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Expr Node
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}
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// NewNullable node constuctor
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func NewNullable(Expression Node) *Nullable {
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return &Nullable{
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Expression,
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}
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}
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// Attributes returns node attributes as map
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func (n *Nullable) Attributes() map[string]interface{} {
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return nil
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}
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// Walk traverses nodes
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// Walk is invoked recursively until v.EnterNode returns true
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func (n *Nullable) Walk(v Visitor) {
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if v.EnterNode(n) == false {
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return
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}
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if n.Expr != nil {
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vv := v.GetChildrenVisitor("Expr")
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n.Expr.Walk(vv)
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}
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v.LeaveNode(n)
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}
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