Szathmáry László honlapja @ DEIK

scope(exit): the expression is always executed when exiting the scope, regardless of whether successfully or due to an exception
scope(success): the expression is executed only if the scope is being exited successfully
scope(failure): the expression is executed only if the scope is being exited due to an exception

(1) example

import std.stdio;
import core.stdc.stdlib;

void main()
{
int* p = cast(int*) malloc(10 * int.sizeof);
scope(exit) free(p); // Ensure cleanup

if (p is null)
{
// Handle allocation failure
writeln("Error: malloc() failed");
return;
}

// Use the memory
p[0] = 42;
writeln(p[0]);
// ... rest of your code
}

Notes:

Here, scope(exit) guarantees that when we leave the scope, the allocated memory will be freed.
D is a garbage-collected language, so there are better alternatives than calling malloc() directly. This is just for the sake of the example.
scope statements can be specified as blocks as well:

scope(exit) {
    free(p); // Ensure cleanup
}

If you have several scope statements, their blocks are executed in reverse order. Imagine that these scope statements are put in a stack data structure.