Class ConstructDisplayName

java.lang.Object
org.ek9lang.compiler.support.ConstructDisplayName
All Implemented Interfaces:
Function<ISymbol, Optional<String>>
public final class ConstructDisplayName extends Object implements Function<ISymbol, Optional<String>>
THE display name of a construct - the name a person reads for it at RUN TIME (F2, Steve 2026-10-08, Contract 21 in EK9_BACKEND_IR_CONTRACTS.md). Use this, never a demangler.

A construct's IDENTITY is its fully qualified name, and for a monomorphised generic that name is a DIGEST (module::_Holder_68EF...): it can never be turned back into Holder of String at run time. So the display name is fixed HERE, at compile time, from the SYMBOL - the generic it parameterises and its type arguments, rendered exactly as the compiler's own friendly name renders them (ToCommaSeparated) - and handed to the back ends as IR data (IRConstruct.getDisplayName()), which store it on the type.

Present ONLY where it differs from the identity: a parameterised type or function. Every other construct has none (its identity already reads correctly), so ordinary classes' IR and bytecode are unchanged. A dynamic class or function (_Class_<hash>) has none either: it has no source name to show.

The fully qualified display name (module::Holder of String) of a monomorphised generic, else empty. A dynamic class or function among its type arguments reads as FriendlyInternalName gives it (Box of cls, never Box of _Class_<digest>), so the run-time name (Ek9TypeName) agrees with the generated $ (ReadableTypeName) - D65. The sort owner's form, digests kept, is DistinctConstructDisplayName; the readable names a generated operator shows are ReadableTypeName and ReadableFriendlyName.

🔑 Display only - never an identity, never a join key: two parameterisations in different modules can share a display name.