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Gives warnings when pattern matches are incomplete, when matches are
redundant (in certain cases), or when no unguarded patterns exist. For
example the following file:
enum Test = {A, C, D}
val test1 : Test -> string
function test1 x =
match x {
A => "match A",
B => "this will match anything, because B is unbound!",
C => "match C",
D => "match D"
}
val test2 : Test -> string
function test2 x =
match x {
A => "match A",
C => "match C"
/* No match for D */
}
val test3 : Test -> string
function test3 x =
match x {
A if false => "never match A",
C => "match C",
D => "match D"
}
val test4 : Test -> string
function test4 x =
match x {
A if true => "match A",
C if true => "match C",
D if true => "match D"
}
will produce the following warnings
Warning: Possible redundant pattern match at file "test.sail", line 10, character 5 to line 10, character 5
C => "match C",
Warning: Possible redundant pattern match at file "test.sail", line 11, character 5 to line 11, character 5
D => "match D"
Warning: Possible incomplete pattern match at file "test.sail", line 17, character 3 to line 17, character 7
match x {
Most general matched pattern is A_|C_
Warning: Possible incomplete pattern match at file "test.sail", line 26, character 3 to line 26, character 7
match x {
Most general matched pattern is C_|D_
Warning: No non-guarded patterns at file "test.sail", line 35, character 3 to line 35, character 7
match x {
warnings can be turned of with the -no_warn flag.
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