CaptureIO is an OCaml library that captures the terminal print outs of a sequence of code or function, in a manner similar to Perl's IO::Capture.
To capture the output of a term wrap it in a lambda that takes unit as argument.
let str = capture (fun () -> print_string "hello") in
assert(str = "hello");Alternatively, you can start a capture session to capture the output of a block of code.
let session = start_capture() in
prerr_string ("error1");
prerr_string ("error2");
let str = (finish_capture session) in
assert(str = "error1error2");It is also possible to capture the output to a specific file descriptor.
let file_chan = Pervasives.open_out "somefile" in
let file_descr = Unix.descr_of_out_channel file_chan in
let session = start_capture_descr [file_descr] in
print_string("not captured");
Pervasives.output_string file_chan "is captured";
let result = finish_capture session in
assert(result = "is captured"); For the full API see the file lib/capturio.mli which is fully documented.
For more examples see the tests in t/01-capture_test.ml.