Confusing parser error for scripting error

[Till Westmann]

This query:

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

declare %an:sequential function local:func($a, $b) {
  if ($a) then {
    ();
  } else {
    if ($b) then {
      ();
      local:func(false(), false()) (: forgot semicolon :)
      local:func(true(), false());
    } else {
      ();
    }
  }
};

local:func(false(), true())

reports this error:

<...>:4,9: static error [err:XPST0003]: invalid expression: syntax error, unexpected ExprSingle (missing comma "," between expressions?)

This is quite difficult to find as
a) the error message does not seem to be related to the problem and
b) the error location points to line 4 while the problem is in line 9

(Of course in the real example there was a lot more code between the error and the indicated error location).

[Till Westmann (tillw)]

Also check the information in bug# 1072644