Class ExternFootprint

java.lang.Object

org.ek9lang.compiler.support.ExternFootprint

All Implemented Interfaces:

Function<String, OptionalInt>

public final class ExternFootprint
extends Object
implements Function<String, OptionalInt>

The native footprint of a field-bearing extern base (Exception, Money, ...), or empty for a user type or a field-less extern type. Such a super declares its state as Java/C struct fields, not EK9 properties, so in the flat field layout (FieldSlots) it contributes this many slots and the walk stops there (InheritedSlotCount). Was FieldSlots.externFootprint (no-statics lane S3, 2026-10-29).

Field Summary

Fields

Modifier and Type	Field	Description
static final Map<String,Integer>	FOOTPRINTS	Fully-qualified extern type name -> its native footprint in 8-byte slots after the object header: (sizeof(C struct) - 32) / 8, clang-measured against the real org_ek9_lang_* structs and held by ExternBaseLayoutDriftTest on the native branch.

Constructor Summary

Constructors

Constructor	Description
ExternFootprint()

Method Summary

Modifier and Type	Method	Description
OptionalInt	apply(String fullyQualifiedTypeName)

Methods inherited from class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface Function

andThen, compose

Field Details

FOOTPRINTS

public static final Map<String,Integer> FOOTPRINTS

Fully-qualified extern type name -> its native footprint in 8-byte slots after the object header: (sizeof(C struct) - 32) / 8, clang-measured against the real org_ek9_lang_* structs and held by ExternBaseLayoutDriftTest on the native branch. A FOOTPRINT, not a field count (Money is __int128 + int8_t + char* = 4 slots). Field-less open extern types (Aspect, FileSystem) are absent: 0. Immutable - the native branch's drift test holds it against the C structs (was FieldSlots.externFootprints()).

Constructor Details

ExternFootprint

public ExternFootprint()

Method Details

apply

public OptionalInt apply(String fullyQualifiedTypeName)

Specified by:

apply in interface Function<String, OptionalInt>