> I thought it was an April Fool's joke because all the links are dead to me:

Well, it's not an April Fool's joke, but the whitepaper certainly had
me laughing. For example, here's how to call out to Blue Ruby to
calculate 7+3:

Report ZABAP_RUBY.

data: BLUERUBY type ref to /SRUBY/IF_BLUERUBY,
      FIXNUM1 type ref to /SRUBY/CL_OBJECT,
      FIXNUM2 type ref to /SRUBY/CL_OBJECT,
      RESULT type ref to /SRUBY/CL_OBJECT,
      ABAP_RESULT type I.

create object BLUERUBY type /SRUBY/CL_BLUERUBY_FACADE.
FIXNUM1 = BLUERUBY->CONVERT_ABAP2RUBY( 7 ).
FIXNUM2 = BLUERUBY->CONVERT_ABAP2RUBY( 3 ).
RESULT = BLUERUBY->CALL_METHOD(
      METHOD_NAME = '+'
      RUBY_RECEIVER_OBJECT = FIXNUM1
      ARGUMENT1 = FIXNUM2 ).
call method BLUERUBY->CONVERT_RUBY2ABAP
  exporting
    RUBY_OBJECT = RESULT
  importing ABAP_DATA = ABAP_RESULT.
write: 'Blue Ruby thinks that 7 + 3 = ', ABAP_RESULT.