diff options
| -rw-r--r-- | src/Util/LockedLet.v | 9 | ||||
| -rw-r--r-- | src/Util/Notations.v | 2 |
2 files changed, 11 insertions, 0 deletions
diff --git a/src/Util/LockedLet.v b/src/Util/LockedLet.v new file mode 100644 index 000000000..088e914fb --- /dev/null +++ b/src/Util/LockedLet.v @@ -0,0 +1,9 @@ +(** * A version of [let] that doesn't disappear under βδζ unless you also have ι and remove opacity *) +Require Import Crypto.Util.Notations. + +Definition locked_let {A} (x : A) : bool * A := (true, x). +Definition unlock_let {A} (x : A) : locked_let x = (true, x) := eq_refl. +Global Opaque locked_let. +Global Arguments locked_let : simpl never. + +Notation "'llet' x := A 'in' b" := (let '(_, x) := locked_let A in b). diff --git a/src/Util/Notations.v b/src/Util/Notations.v index 22ddf854c..99761c63b 100644 --- a/src/Util/Notations.v +++ b/src/Util/Notations.v @@ -63,6 +63,8 @@ Reserved Notation "'plet' x := y 'in' z" (at level 200, z at level 200, format "'plet' x := y 'in' '//' z"). Reserved Notation "'slet' x := A 'in' b" (at level 200, b at level 200, format "'slet' x := A 'in' '//' b"). +Reserved Notation "'llet' x := A 'in' b" + (at level 200, b at level 200, format "'llet' x := A 'in' '//' b"). (* Note that making [Let] a keyword breaks the vernacular [Let] in Coq 8.4 *) Reserved Notation "'dlet' x := y 'in' f" (at level 200, f at level 200, format "'dlet' x := y 'in' '//' f"). |