CREATE OR REPLACE FUNCTION test.plr_do(text)
RETURNS void LANGUAGE plr IMMUTABLE AS $$
try = try ( {
    p = parse(text = arg1)
    e = eval(p)
    cap = capture.output (e)
}, silent=T)

if (inherits(try, 'try-error')) {
    pg.throwerror(try[1])
} else {
    for (m in cap) pg.thrownotice (m)
}
$$;

-- Example 1
DO $$
BEGIN
PERFORM test.plr_do('
    options(show.signif.stars = F)
    x = runif(100)
    y = runif(100)
    model = lm(y ~ x)
    print(summary(model))
');
END $$;

-- Example 2
-- Show blank output first (useless)
SELECT test.plr_do('
    x = runif(100)
    y = runif(100)
    model = lm(y ~ x)
    print(summary(model))
');

-- Example 3
-- with error
DO $$
BEGIN
PERFORM test.plr_do('
    x = rand(100)
    y = rand(100)
    model = lm(y ~ x)
    print(summary(model))
');
END $$;