Member predicate Compilation::getArgument

Gets the ith argument passed to the extractor on this invocation.

If the compiler was invoked as gcc -c f1.c f2.c f3.c then this will typically hold for

i | result

• | — 0 | path to extractor 1 | --mimic 2 | /usr/bin/gcc 3 | -c 4 | f1.c 5 | f2.c 6 | f3.c