26 Jul
2013
26 Jul
'13
12:15 p.m.
On 07/23/2013 03:37 PM, i c wrote:
let's consider the following:
let fd = Unix.open ... let fd = Unix.open ...
At this point one file descriptor cannot be closed. Static analysis will have trouble catching these bugs, so do humans. Disallowing variable shadowing prevents this. The two "fd" occur in different contexts and should have different names.
$ cat shadow_fd.ml let () = let fd = Unix.openfile "foo_1.txt" [] 0o640 in let fd = Unix.openfile "foo_2.txt" [] 0o640 in Unix.close fd $ ocamlfind ocamlopt -linkpkg -package unix shadow_fd.ml -o shadow_fd File "shadow_fd.ml", line 2, characters 6-8: Warning 26: unused variable fd.