version(tag) and version(level)

version is similar to debug and is used in the same way:

version(testRelease) /* ... an expression ... */;

version(schoolRelease) {
    /* ... expressions that are related to the version of
    * this program that is presumably shipped to schools ... */

} else {
    // ...  code compiled otherwise ...
}

version(1) aVariable = 5;

version(2) {
    // ... a feature of version 2 ...
}

The else clause is optional.

Although version works essentially the same as debug, having separate keywords helps distinguish their unrelated uses.

As with debug, more than one version can be enabled:

$ dmd deneme.d -w -version=record -version=precise_calculation

There are many predefined version tags, the complete list of which is available at the conditional compilation specification. The following short list is just a sampling: