Added pattern guards to sail

Introduces a when keyword for case statements, as the Pat_when constructor for pexp's in the AST. This allows us to write things like:

typedef T = const union { int C1; int C2 }

function int test ((int) x, (T) y) =
  switch y {
    case (C1(z)) when z == 0 -> 0
    case (C1(z)) when z != 0 -> x quot z
    case (C2(z)) -> z
  }

this should make translation from ASL's patterns much more straightforward

0 files changed, 0 insertions, 0 deletions