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Pavel V. Talanov 59f192ef90 Replace 'class object' with 'default object' in renderers and test data

Includes changes to decompiled text
Old syntax is used in builtins and project code for now

2015-03-06 19:36:54 +03:00

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Support for JVM's ACC_NATIVE flag

Goal: enable JNI interop for Kotlin, so that anything that works through JNI in Java could be reproduced 1-to-1 in Kotlin

Syntax

The following definition is present in the library:

package kotlin.jvm

Retention(RetentionPolicy.SOURCE)
public annotation class native

This annotation is applicable to

functions
property accessors

A declaration marked with this annotation is referred to as a native declaration.

Checks to perform:

a native declaration can not be abstract
a native declaration can not have a body
a native declaration can not be marked inline
a native declaration can not have reified type parameters NOTE: this is achieved through prohibiting inline, as reified is only allowed on inline-functions now
members of traits can not be native

NOTE: native members can override open (or abstract) members of supertypes

Semantics on the JVM

Intuition: a JVM method whose source declaration is native is marked with the ACC_NATIVE flag, and has no CODE attribute.

Interaction with [platformStatic]

A native member of an object marked native and platformStatic is translated in a straightforward way: there is only one JVM method corresponding to it, and it is marked as ACC_NATIVE.

A member of a default object of class C marked native and platformStatic yields two JVM methods:

static member of C that is marked ACC_NATIVE;
instance member of C$object that is not marked ACC_NATIVE and its body delegates to the native static method.

Top-level declarations

A native member of package p yields one JVM method:

member of a package-facade class PPackage which is marked with ACC_NATIVE flag.

Native Property Accessors

A property can not be marked native. A property accessor can be marked native if it has no body (i.e. it is a default accessor). In this case the generated code is the same as for a native function defined in the same context as the property.

Example:

val foo: Int
  [native] get

Not implemented (yet)

native property accessors
frontend: when accessors are default and native, don't require an initializer, don't allow a backing field
backend: when accessors are default and native, don't generate a backing field
applicability checks: only functions and property accessors

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