59 lines
1.2 KiB
Go
59 lines
1.2 KiB
Go
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package kong
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import (
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"fmt"
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)
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// Next should be called by Visitor to proceed with the walk.
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//
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// The walk will terminate if "err" is non-nil.
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type Next func(err error) error
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// Visitor can be used to walk all nodes in the model.
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type Visitor func(node Visitable, next Next) error
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// Visit all nodes.
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func Visit(node Visitable, visitor Visitor) error {
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return visitor(node, func(err error) error {
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if err != nil {
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return err
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}
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switch node := node.(type) {
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case *Application:
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return visitNodeChildren(node.Node, visitor)
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case *Node:
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return visitNodeChildren(node, visitor)
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case *Value:
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case *Flag:
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return Visit(node.Value, visitor)
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default:
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panic(fmt.Sprintf("unsupported node type %T", node))
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}
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return nil
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})
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}
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func visitNodeChildren(node *Node, visitor Visitor) error {
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if node.Argument != nil {
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if err := Visit(node.Argument, visitor); err != nil {
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return err
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}
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}
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for _, flag := range node.Flags {
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if err := Visit(flag, visitor); err != nil {
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return err
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}
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}
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for _, pos := range node.Positional {
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if err := Visit(pos, visitor); err != nil {
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return err
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}
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}
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for _, child := range node.Children {
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if err := Visit(child, visitor); err != nil {
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return err
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}
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}
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return nil
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}
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