NotNull

A NotNull type ensure that the type you give it can never have a null value. So it is always safe to use. It's specifically designed for pointers to values or classes. You can give it a struct as well.

The one thing to watch out for is inner classes or structs. Since notNull is a template function, and it ensures that a type T is always created, it has to allocate memory. But inner classes and structs need a context pointer to be newed, so this only works with static inner classes and structs.

the constructor is disabled, so you have to use the function notNull to construct NotNull objects.

struct NotNull (

) if (

is(T == class) ||

is(T == interface)

isPointer!T

) {

enum bool isPointer(T); via import std.traits : isPointer;;

import optional : isNotNull;;

inout(T) value [@property getter];

void opAssign(typeof(null) );

this();

this(NotNull!V other);

void opAssign(NotNull!V other);

}

Constructors

this this(): Undocumented in source.
this this(NotNull!V other): You can only init from another NotNull type.

opAssign void opAssign(NotNull!V other): You can only asign to another NotNull type.
opAssign void opAssign(typeof(null) ): Undocumented in source.

Properties

value inout(T) value [@property getter]: Undocumented in source. Be warned that the author may not have intended to support it.

Examples

static class C { int i; void f() { i = 3; } }
static struct S { int i; void f() { i = 3; } }

void f0(NotNull!C c) {
    c.f();
}

void f1(NotNull!(S*) sp) {
    sp.f();
}

auto c = notNull!C;
auto sp = notNull!(S*);

f0(c);
f1(sp);

assert(c.i == 3);
assert(sp.i == 3);

NotNull

Constructors

Alias This

Members

Functions

Properties

Examples

Meta

Source