38 lines
900 B
V
38 lines
900 B
V
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module walker
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import toml.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) ?
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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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i.inspector_callback(node, i.data) or { return err }
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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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if node is map[string]ast.Node {
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n := node as map[string]ast.Node
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for _, nn in n {
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walk(visitor, &nn) ?
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}
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} else {
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visitor.visit(node) ?
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}
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}
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