Step 6 : Grading functions for variables
Warning This step is ahead of the current version of [learn-ocaml].
Test functions for variables
There are 3 test functions for variables.
Signatures
val test_variable :
'a Ty.ty -> string -> 'a -> Learnocaml_report.report
val test_variable_against_solution :
'a Ty.ty -> string -> Learnocaml_report.report
val test_variable_property :
'a Ty.ty -> string -> ('a -> Learnocaml_report.report) -> Learnocaml_report.report
Examples
Trivial example with grade_variable
grade_variable
is usually used only for trivial examples since
it is directly compared to an expected result and not to a solution.
let exercise_0 =
grade_variable [%ty: int] "forty_two" 42
More classical example with grade_variable_against_solution
grade_variable_against_solution
is more versatile and works
basically like test_function_against_solution
.
let exercise_1 =
grade_variable_against_solution [%ty: float] "norm"
grade_variable_property
grade_variable_property
is used in specific cases when you
want to write your own report depending on the value of the graded
variable.
let exercise_2 =
grade_variable_property [%ty: side] "s"
(
fun s ->
match s with
| Right -> if vect.x > 0. then
[ Message ([ Text "Expected value"] , Success 1) ]
else if vect.x = 0. then
[ Message ([ Text "Wrong value"] , Failure) ;
Message ([ Text "The answer should "; Code "Middle" ; Text "."] , Informative) ]
else
[ Message ([ Text "Wrong value"] , Failure) ;
Message ([ Text "The answer should "; Code "Left" ; Text "."] , Informative) ]
| Left -> if vect.x < 0. then
[ Message ([ Text "Expected value"] , Success 1) ]
else if vect.x = 0. then
[ Message ([ Text "Wrong value"] , Failure) ;
Message ([ Text "The answer should "; Code "Middle" ; Text "."] , Informative) ]
else
[ Message ([ Text "Wrong value"] , Failure) ;
Message ([ Text "The answer should "; Code "Right" ; Text "."] , Informative) ]
| Middle -> if vect.x = 0. then
[ Message ([ Text "Expected value"] , Success 1) ]
else if vect.x > 0. then
[ Message ([ Text "Wrong value"] , Failure) ;
Message ([ Text "The answer should "; Code "Right" ; Text "."] , Informative) ]
else
[ Message ([ Text "Wrong value"] , Failure) ;
Message ([ Text "The answer should "; Code "Left" ; Text "."] , Informative) ]
)