Class ExternSymbols

java.lang.Object
org.ek9lang.compiler.support.ExternSymbols
public final class ExternSymbols extends Object
THE test for "is this symbol provided from OUTSIDE this workspace's EK9 source?" — a built-in, or any member of an extern construct. Use it before turning a symbol's source token into a location shown to a user; do not re-derive the EXTERN check.

Why this matters, concretely. A built-in symbol has a perfectly good source token, and that token's source name is a file that DOES NOT EXIST. The bootstrap constructs its source in memory as new CompilableSource(".", "org-ek9-lang.ek9", ...) (Ek9BuiltinIntrospectionSupplier), so a Go-to-Definition on String.trim() that trusts the token resolves to <cwd>/org-ek9-lang.ek9 at a synthetic line — a path no editor can open. The symbol is real; the FILE is not. Nothing about the token itself says so, which is exactly why this has to be an explicit check rather than something a caller notices.

Why it is shared (2026-09-13). ReferencesExtractor had this as a private method and guarded correctly; compiler-ide's NavigationProvider had no such check at all, so the IDE's Go-to-Definition on any built-in navigated to a non-existent file. Two consumers of the same rule, one of them wrong, is precisely the shape that a copied predicate produces — so it is now one function in the lowest module, visible to compiler-services and compiler-ide alike.

⚠️ The owner check is DEFENCE, and its triggering shape is unverified. An earlier version of this javadoc asserted that "a method is not itself marked EXTERN; its owning aggregate is" — that is FALSE for built-ins, and falsification caught it: removing the owner branch left the test green. Measured on org.ek9.lang::String.trim(), the method AND the aggregate both carry EXTERN = TRUE, so the first branch alone is sufficient there. The owner branch is retained because it came from ReferencesExtractor's original private guard and removing it would be a silent behaviour change to a well-tested consumer — but which shape needs it (a user-declared defines extern module, most likely) has NOT been established. Establish it before relying on it, and do not restate the claim this paragraph replaced.

  • Method Details

    • isExternallyProvided

      public static boolean isExternallyProvided(ISymbol symbol)
      Is this symbol externally provided, so its source token must NOT be shown as a location?
      Parameters:
      symbol - the symbol to test; null is not external (there is nothing to show anyway)
      Returns:
      true when the symbol, or the aggregate owning it, is marked EXTERN