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为什么在添加捕获元素时以下 lambda 不遵守签名?
[&callback](unsigned handle, void* userData, void* data, unsigned size) -> void { ... }
但这会吗?
[](unsigned handle, void* userData, void* data, unsigned size) -> void { ... }
签名:
typedef void (*em_async_wget2_data_onload_func)(unsigned, void*, void*, unsigned);