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require_ 'macro.try'
local check
try
try
if arg[1] then error('throw!') end
except(err)
print('shd be throw',err)
end
a.x = 0
except(e)
check = e
end
-- the truly tricky case here is the plain return, since we need to distinguish
-- it from merely leaving the protected block.
function testtry(n)
try
if n == 0 then return 'cool'
elseif n == 1 then return 'cool',42
elseif n == 2 then return --aha
elseif n == 3 then
error('throw baby!')
end
except(msg)
return nil,msg
end
return 42,'answer'
end
function match (x,y)
local ok
if type(x) == 'string' and type(y) == 'string' then
ok = y:find(x)
else
ok = x == y
end
if not ok then print('mismatch',x,y) end
return ok
end
function assert2 (x1,x2,y1,y2)
assert(match(x1,y1) and match(x2,y2))
end
assert(match("attempt to index global 'a' %(a nil value%)$",check))
assert2('cool',nil,testtry(0))
assert2('cool',42,testtry(1))
assert2(42,'answer',testtry(2))
assert2(nil,'throw baby!$',testtry(3))
assert2(42,'answer',testtry(4))
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