1 files changed, 10 insertions, 0 deletions
diff --git a/lib/std/logic.nim b/lib/std/logic.nim
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+## This module provides further logic operators like 'forall' and 'exists'
+## They are only supported in ``.ensures`` etc pragmas.
+
+proc `->`*(a, b: bool): bool {.magic: "Implies".}
+proc `<->`*(a, b: bool): bool {.magic: "Iff".}
+
+proc forall*(args: varargs[untyped]): bool {.magic: "Forall".}
+proc exists*(args: varargs[untyped]): bool {.magic: "Exists".}
+
+proc old*[T](x: T): T {.magic: "Old".}