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Interpretable modules are modules for which a .beam file, compiled with option debug_info set, is located in the same directory as the source code, or in an ebin directory next to it.
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Modules for which these requirements are not fulfilled are not interpretable and are therefore displayed within parentheses.
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Option debug_info causes debug information or abstract code to be added to the .beam file. This increases the file size and makes it possible to reconstruct the source code. It is therefore recommended not to include debug information in code aimed for target systems.
翻译：以 .beam结尾的文件模块就是编译时通过 debug_info选项位于同目录下或者ebin目录下编译出来的可解析模块。不用这些要求实现的模块在debugger中会用括号展示。debug_info选项使得调试信息或者抽象码加到.beam文件中，这能减少文件大小且能让代码重构（即通过beam文件还原源代码，具体做法可在这找到）成为可能。因此不推荐在目标应用系统中使用debug information。