Malformed Array Literal in PL/pgSQL Exception Block

Hackers,

I’ve been happily using the array-to-element concatenation operator || to append a single value to an array, e.g,

SELECT array || 'foo';

And it works great, including in PL/pgSQL functions, except in an exception block. When I run this:

BEGIN;

CREATE OR REPLACE FUNCTION foo(
) RETURNS BOOLEAN IMMUTABLE LANGUAGE PLPGSQL AS $$
DECLARE
things TEXT[] := '{}';
BEGIN
things := things || 'foo';
RAISE division_by_zero;
EXCEPTION WHEN OTHERS THEN
things := things || 'bar';
END;
$$;

SELECT foo();

ROLLBACK;

The output is:

psql:array.sql:15: ERROR: malformed array literal: "bar"
LINE 1: SELECT things || 'bar'
^
DETAIL: Array value must start with "{" or dimension information.
QUERY: SELECT things || 'bar'
CONTEXT: PL/pgSQL function foo() line 8 at assignment

Note that it’s fine with the use of || outside the exception block, but not inside! I’ve worked around this by using `things || '{bar}'` instead, but it seems like a bug or perhaps unforeseen corner case that appending a value to an array doesn’t work in an exception-handling block.

Best,

David