E03030: reference does not resolve

What went wrong

A 'references' statement points to a module or type that doesn't exist. The compiler cannot find what you're trying to import.

Worked examples

Compilable examples demonstrating this error and the correct fix:

• ek9 -q 1308 (Why does my references statement fail with E03030 refe...)

Common causes

1. Typo in module path: typo.in.module::MyClass vs actual.module::MyClass
2. Typo in type name: module::MyClss vs module::MyClass
3. Module not compiled/available:

• Dependency not in compile path
• Module file not in expected location

1. Wrong module for the type:

• Type exists but in different module than specified

1. The module named only IMPORTS it:

• 'references beta::Widget' where beta itself only has 'references delta::Widget'. A reference is shorthand inside the importing module; it is never re-exported. Reference the module that DEFINES it - the error message names it: delta::Widget

How to fix it

• Verify the exact module path and type name
• Check that the source module compiles successfully
• Ensure dependency is in your compile path
• Use IDE autocomplete to find correct path

Verification

• Compile the dependency module first
• Check the module's 'defines' sections for exported types
• Ensure types are not marked private

See also

• E03030: Reference doesn't RESOLVE (import time)
• E50001: Identifier doesn't resolve (use time)
• E01010: Invalid reference FORMAT (missing ::)

Examples

Every example is compiled by the EK9 compiler: the first fails exactly as captioned, the others fix it.

Fails with E03030: reference does not resolve

#!ek9
defines module error.e03030.bad

  references
    //No module of that name is in the compile
    com.nonexistent.module::Helper
    //The module exists, but holds no construct of that name
    org.ek9.lang::Helper

  defines function

    describe()
      <- rtn as String: "nothing to help with"

Fixed: Reference a construct a module in the compile really defines, spelled exactly

#!ek9
defines module error.e03030.good

  references
    error.e03030.good.utilities::Helper

  defines function

    describe()
      <- rtn as String: Helper().describe()

Fixed: The module it comes from must be part of the compile

#!ek9
defines module error.e03030.good.utilities

  defines class

    Helper
      describe()
        <- rtn as String: "a helper"

Questions and answers

These Q&A entries show E03030 and its fix:

• Q1308: Why does my references statement fail with E03030 reference does not resolve?