42 lines
702 B
Go
42 lines
702 B
Go
package main
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type Environment struct {
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values map[string]any
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parent *Environment
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}
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func newEnvironment(parent *Environment) *Environment {
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return &Environment{values: map[string]any{}, parent: parent}
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}
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func (env *Environment) get(key string) any {
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if found, ok := env.values[key]; ok {
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return found
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}
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if env.parent != nil {
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return env.parent.get(key)
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}
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return nil
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}
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func (env *Environment) exists(key string) bool {
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_, ok := env.values[key]
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if !ok && env.parent != nil {
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return env.parent.exists(key)
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}
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return ok
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}
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func (env *Environment) set(key string, val any) {
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if env.parent != nil && env.parent.exists(key) {
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env.parent.set(key, val)
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}
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env.values[key] = val
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}
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