# #ifdef directive

Source: https://ref.dm-lang.org/DM/preprocessor/ifdef

### Format
> `#ifdef Name`

### Args
> Name: A macro definition.

The `#ifdef` statement is used to conditionally compile code. It is equivalent to `#if defined(Name)`.

### See also
- [#define directive](https://ref.dm-lang.org/DM/preprocessor/define/index.md)
- [#if directive](https://ref.dm-lang.org/DM/preprocessor/if.md)
- [#ifndef directive](https://ref.dm-lang.org/DM/preprocessor/ifndef.md)