misplaced compiler error

[Paul J. Lucas]

Given:

(:===== CUT =====:)
jsoniq version "1.0";

declare namespace an = "http://www.zorba-xquery.com/annotations";

declare %an:sequential function local:same-sentence( $tokens as object* )
  as xs:boolean
{
  let $head := head( $tokens )
  for $t in tail( $tokens ) { (: <-- missing "return" here :)
    if ( $t.sentence ne $head.sentence )
    then exit returning false;
    else ;
  }
  true
};

let $tokens := (
  { "sentence" : 1 },
  { "sentence" : 1 },
  { "sentence" : 2 }
)
return local:same-sentence( $tokens )
(:===== CUT =====:)

one gets:

</tmp/x.jq>:3,65: static error [err:XPST0003]: invalid expression: syntax error, missing semicolon ";" after statement.; raised at /Users/pjl/src/flwor/zorba/repo/bug-1187161/zorba/src/compiler/api/compiler_api.cpp:253

The actual error is the missing "return" in the "for", but the compiler instead complains about the ';' that is present despite it's complaint.