51 lines
1.1 KiB
Go
51 lines
1.1 KiB
Go
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package participle
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import "fmt"
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// Visit all nodes.
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//
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// Cycles are deliberately not detected, it is up to the visitor function to handle this.
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func visit(n node, visitor func(n node, next func() error) error) error {
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return visitor(n, func() error {
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switch n := n.(type) {
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case *disjunction:
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for _, child := range n.nodes {
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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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case *strct:
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return visit(n.expr, visitor)
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case *sequence:
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if err := visit(n.node, visitor); err != nil {
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return err
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}
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if n.next != nil {
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return visit(n.next, visitor)
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}
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return nil
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case *parseable:
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return nil
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case *capture:
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return visit(n.node, visitor)
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case *reference:
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return nil
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case *optional:
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return visit(n.node, visitor)
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case *repetition:
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return visit(n.node, visitor)
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case *negation:
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return visit(n.node, visitor)
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case *literal:
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return nil
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case *group:
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return visit(n.expr, visitor)
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case *lookaheadGroup:
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return visit(n.expr, visitor)
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default:
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panic(fmt.Sprintf("%T", n))
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}
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})
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}
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