38 lines
879 B
V
38 lines
879 B
V
module walker
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import v.ast
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// Visitor defines a visit method which is invoked by the walker in each node it encounters.
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pub interface Visitor {
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visit(node ast.Node) ?
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}
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pub type InspectorFn = fn (node ast.Node, data voidptr) bool
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struct Inspector {
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inspector_callback InspectorFn
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mut:
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data voidptr
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}
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pub fn (i &Inspector) visit(node ast.Node) ? {
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if i.inspector_callback(node, i.data) {
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return
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}
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return error('')
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}
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// inspect traverses and checks the AST node on a depth-first order and based on the data given
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pub fn inspect(node ast.Node, data voidptr, inspector_callback InspectorFn) {
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walk(Inspector{inspector_callback, data}, node)
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}
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// walk traverses the AST using the given visitor
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pub fn walk(visitor Visitor, node ast.Node) {
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visitor.visit(node) or { return }
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children := node.children()
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for child_node in children {
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walk(visitor, &child_node)
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}
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}
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