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-- file: example.lua
---- importing ----
if string.sub(_VERSION,1,7)=='Lua 5.0' then
-- lua5.0 doesnt have a nice way to do this
lib=loadlib('example.dll','luaopen_example') or loadlib('example.so','luaopen_example')
assert(lib)()
else
-- lua 5.1 does
require('example')
end
-- throw a lot of exceptions:
-- you must catch exceptions using pcall and then checking the result
t = example.Test()
print "calling t:unknown()"
ok,res=pcall(function() t:unknown() end)
if ok then
print " that worked! Funny"
else
print(" call failed with error:",res)
end
print "calling t:simple()"
ok,res=pcall(function() t:simple() end)
if ok then
print " that worked! Funny"
else
print(" call failed with error:",res)
end
print "calling t:message()"
ok,res=pcall(function() t:message() end)
if ok then
print " that worked! Funny"
else
print(" call failed with error:",res)
end
print "calling t:hosed()"
ok,res=pcall(function() t:hosed() end)
if ok then
print " that worked! Funny"
else
print(" call failed with error:",res.code,res.msg)
end
-- this is a rather strange way to perform the multiple catch of exceptions
print "calling t:mutli()"
for i=1,3 do
ok,res=pcall(function() t:multi(i) end)
if ok then
print " that worked! Funny"
else
if swig_type(res)=="Exc *" then
print(" call failed with Exc exception:",res.code,res.msg)
else
print(" call failed with error:",res)
end
end
end
-- this is a bit crazy, but it shows obtaining of the stacktrace
function a()
b()
end
function b()
t:message()
end
print [[
Now let's call function a()
which calls b()
which calls into C++
which will throw an exception!]]
ok,res=pcall(a)
if ok then
print " that worked! Funny"
else
print(" call failed with error:",res)
end
print "Now let's do the same using xpcall(a,debug.traceback)"
ok,res=xpcall(a,debug.traceback)
if ok then
print " that worked! Funny"
else
print(" call failed with error:",res)
end
print "As you can see, the xpcall gives a nice stacktrace to work with"
ok,res=pcall(a)
print(ok,res)
ok,res=xpcall(a,debug.traceback)
print(ok,res)
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