26 lines
616 B
Go
26 lines
616 B
Go
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// op-registry.go
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package expr
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const initialRegistryCapacity = 10
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type termContructor func(tk *Token) *term
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var constructorRegistry map[Symbol]termContructor = nil
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func registerTermConstructor(sym Symbol, constructor termContructor) {
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if constructorRegistry == nil {
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constructorRegistry = make(map[Symbol]termContructor, initialRegistryCapacity)
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}
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constructorRegistry[sym] = constructor
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}
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func newTerm(tk *Token, parent *term) (inst *term) {
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if constructorRegistry != nil {
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if construct, exists := constructorRegistry[tk.Sym]; exists {
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inst = construct(tk)
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inst.setParent(parent)
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}
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}
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return
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}
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