# #pragma

`#pragma` was introduced to remove dependency on [#ifdef](/_/cpp/code/pre-processors/ifdef.md) for solely including header file.

```cpp
// In myheader.h
#ifndef MYHEADER_H
#define MYHEADER_H

// Header contents go here

#endif // MYHEADER_H
```

Above, as we can see here we are using `#ifndef` for including header files only once, but here we need to declare a Macro = `MYHEADER_H` to chieve this.

To overcome this unnecessary creation of a Macro, we can use `#pragma once` which does the same thing without declaring any Macro.


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