lean4-htt/src/Init/Notation.lean
Leonardo de Moura c9b42af537 chore: (prepare to) rename if-then-else parsers
We also add formatting directives to the new if-then-else parsers.
2020-12-24 08:20:07 -08:00

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/-
Copyright (c) 2020 Microsoft Corporation. All rights reserved.
Released under Apache 2.0 license as described in the file LICENSE.
Authors: Leonardo de Moura
Notation for operators defined at Prelude.lean
-/
prelude
import Init.Prelude
-- DSL for specifying parser precedences and priorities
namespace Lean.Parser.Syntax
syntax:65 (name := addPrec) prec " + " prec:66 : prec
syntax:65 (name := subPrec) prec " - " prec:66 : prec
syntax:65 (name := addPrio) prio " + " prio:66 : prio
syntax:65 (name := subPrio) prio " - " prio:66 : prio
end Lean.Parser.Syntax
macro "max" : prec => `(1024) -- maximum precedence used in term parsers
macro "lead" : prec => `(1023)
macro "(" p:prec ")" : prec => p
macro "min" : prec => `(10) -- minimum precedence used in term parsers
macro "min1" : prec => `(11) -- `(min+1) we can only `min+1` after `Meta.lean`
/-
`max:prec` as a term. It is equivalent to `evalPrec! max` for `evalPrec!` defined at `Meta.lean`.
We use `maxPrec!` to workaround bootstrapping issues. -/
macro "maxPrec!" : term => `(1024)
macro "default" : prio => `(1000)
macro "low" : prio => `(100)
macro "high" : prio => `(10000)
macro "(" p:prio ")" : prio => p
-- Basic notation for defining parsers
syntax stx "+" : stx
syntax stx "*" : stx
syntax stx "?" : stx
syntax:2 stx " <|> " stx:1 : stx
macro_rules
| `(stx| $p +) => `(stx| many1($p))
| `(stx| $p *) => `(stx| many($p))
| `(stx| $p ?) => `(stx| optional($p))
| `(stx| $p₁ <|> $p₂) => `(stx| orelse($p₁, $p₂))
/- Comma-separated sequence. -/
macro:max x:stx ",*" : stx => `(stx| sepBy($x, ",", ", "))
macro:max x:stx ",+" : stx => `(stx| sepBy1($x, ",", ", "))
/- Comma-separated sequence with optional trailing comma. -/
macro:max x:stx ",*,?" : stx => `(stx| sepBy($x, ",", ", ", allowTrailingSep))
macro:max x:stx ",+,?" : stx => `(stx| sepBy1($x, ",", ", ", allowTrailingSep))
macro "!" x:stx : stx => `(stx| notFollowedBy($x))
syntax (name := rawNatLit) "natLit! " num : term
infixr:90 " ∘ " => Function.comp
infixr:35 " × " => Prod
infixl:65 " + " => HAdd.hAdd
infixl:65 " - " => HSub.hSub
infixl:70 " * " => HMul.hMul
infixl:70 " / " => HDiv.hDiv
infixl:70 " % " => HMod.hMod
infixr:80 " ^ " => HPow.hPow
prefix:100 "-" => Neg.neg
-- declare ASCII alternatives first so that the latter Unicode unexpander wins
infix:50 " <= " => HasLessEq.LessEq
infix:50 " ≤ " => HasLessEq.LessEq
infix:50 " < " => HasLess.Less
infix:50 " >= " => GreaterEq
infix:50 " ≥ " => GreaterEq
infix:50 " > " => Greater
infix:50 " = " => Eq
infix:50 " == " => BEq.beq
infix:50 " ~= " => HEq
infix:50 " ≅ " => HEq
infixr:35 " /\\ " => And
infixr:35 " ∧ " => And
infixr:30 " \\/ " => Or
infixr:30 " " => Or
notation:max "¬" p:40 => Not p
infixl:35 " && " => and
infixl:30 " || " => or
notation:max "!" b:40 => not b
infixl:65 " ++ " => HAppend.hAppend
infixr:67 " :: " => List.cons
infixr:20 " <|> " => HOrElse.hOrElse
infixr:60 " >> " => HAndThen.hAndThen
infixl:55 " >>= " => Bind.bind
infixl:60 " <*> " => Seq.seq
infixl:60 " <* " => SeqLeft.seqLeft
infixr:60 " *> " => SeqRight.seqRight
infixr:100 " <$> " => Functor.map
syntax (name := «termIf__:_Then_Else_») ppGroup(ppDedent("if " ident " : " term " then" ppLine term ppDedent(ppLine "else") ppLine term)) : term
macro_rules
| `(if $h:ident : $c then $t:term else $e:term) => `(dite $c (fun $h:ident => $t) (fun $h:ident => $e))
syntax (name := termDepIfThenElse) (priority := high) ppGroup(ppDedent("if " ident " : " term " then" ppLine term ppDedent(ppLine "else") ppLine term)) : term
macro_rules[termDepIfThenElse]
| `(if $h:ident : $c then $t:term else $e:term) => `(dite $c (fun $h:ident => $t) (fun $h:ident => $e))
syntax (name := termIf_Then_Else_) ppGroup(ppDedent("if " term " then" ppLine term ppDedent(ppLine "else") ppLine term)) : term
macro_rules
| `(if $c then $t:term else $e:term) => `(ite $c $t $e)
syntax (name := termIfThenElse) (priority := high) ppGroup(ppDedent("if " term " then" ppLine term ppDedent(ppLine "else") ppLine term)) : term
macro_rules[termIfThenElse]
| `(if $c then $t:term else $e:term) => `(ite $c $t $e)
macro "if " "let " pat:term " := " d:term " then " t:term " else " e:term : term =>
`(match $d:term with | $pat:term => $t | _ => $e)
syntax:min term "<|" term:min : term
macro_rules
| `($f $args* <| $a) => let args := args.push a; `($f $args*)
| `($f <| $a) => `($f $a)
syntax:min term "|>" term:min1 : term
macro_rules
| `($a |> $f $args*) => let args := args.push a; `($f $args*)
| `($a |> $f) => `($f $a)
-- Haskell-like pipe <|
-- Note that we have a whitespace after `$` to avoid an ambiguity with the antiquotations.
syntax:min term atomic("$" ws) term:min : term
macro_rules
| `($f $args* $ $a) => let args := args.push a; `($f $args*)
| `($f $ $a) => `($f $a)
syntax "{ " ident (" : " term)? " // " term " }" : term
macro_rules
| `({ $x : $type // $p }) => `(Subtype (fun ($x:ident : $type) => $p))
| `({ $x // $p }) => `(Subtype (fun ($x:ident : _) => $p))
/-
`withoutExpected! t` instructs Lean to elaborate `t` without an expected type.
Recall that terms such as `match ... with ...` and `⟨...⟩` will postpone elaboration until
expected type is known. So, `withoutExpected!` is not effective in this case. -/
macro "withoutExpectedType! " x:term : term => `(let aux := $x; aux)
syntax "[" term,* "]" : term
syntax "%[" term,* "|" term "]" : term -- auxiliary notation for creating big list literals
namespace Lean
macro_rules
| `([ $elems,* ]) => do
let rec expandListLit (i : Nat) (skip : Bool) (result : Syntax) : MacroM Syntax := do
match i, skip with
| 0, _ => pure result
| i+1, true => expandListLit i false result
| i+1, false => expandListLit i true (← `(List.cons $(elems.elemsAndSeps[i]) $result))
if elems.elemsAndSeps.size < 64 then
expandListLit elems.elemsAndSeps.size false (← `(List.nil))
else
`(%[ $elems,* | List.nil ])
namespace Parser.Tactic
syntax (name := intro) "intro " notFollowedBy("|") (colGt term:max)* : tactic
syntax (name := intros) "intros " (colGt (ident <|> "_"))* : tactic
syntax (name := revert) "revert " (colGt ident)+ : tactic
syntax (name := clear) "clear " (colGt ident)+ : tactic
syntax (name := subst) "subst " (colGt ident)+ : tactic
syntax (name := assumption) "assumption" : tactic
syntax (name := apply) "apply " term : tactic
syntax (name := exact) "exact " term : tactic
syntax (name := refine) "refine " term : tactic
syntax (name := refine!) "refine! " term : tactic
syntax (name := case) "case " ident " => " tacticSeq : tactic
syntax (name := allGoals) "allGoals " tacticSeq : tactic
syntax (name := focus) "focus " tacticSeq : tactic
syntax (name := skip) "skip" : tactic
syntax (name := done) "done" : tactic
syntax (name := traceState) "traceState" : tactic
syntax (name := failIfSuccess) "failIfSuccess " tacticSeq : tactic
syntax (name := generalize) "generalize " atomic(ident " : ")? term:51 " = " ident : tactic
syntax (name := paren) "(" tacticSeq ")" : tactic
syntax (name := withReducible) "withReducible " tacticSeq : tactic
syntax (name := withReducibleAndInstances) "withReducibleAndInstances " tacticSeq : tactic
syntax (name := first) "first " "|"? sepBy1(tacticSeq, "|") : tactic
macro "try " t:tacticSeq : tactic => `(first $t | skip)
macro:1 x:tactic " <;> " y:tactic:0 : tactic => `(tactic| focus ($x:tactic; allGoals $y:tactic))
macro "rfl" : tactic => `(exact rfl)
macro "decide!" : tactic => `(exact decide!)
macro "admit" : tactic => `(exact sorry)
syntax locationWildcard := "*"
syntax locationTarget := "⊢" <|> "|-"
syntax locationHyp := (colGt ident)+
syntax location := withPosition("at " locationWildcard <|> locationTarget <|> locationHyp)
syntax (name := change) "change " term (location)? : tactic
syntax (name := changeWith) "change " term " with " term (location)? : tactic
syntax rwRule := ("←" <|> "<-")? term
syntax rwRuleSeq := "[" rwRule,+,? "]"
syntax (name := rewrite) "rewrite " rwRule (location)? : tactic
syntax (name := rewriteSeq) (priority := high) "rewrite " rwRuleSeq (location)? : tactic
syntax (name := erewrite) "erewrite " rwRule (location)? : tactic
syntax (name := erewriteSeq) (priority := high) "erewrite " rwRuleSeq (location)? : tactic
syntax (name := rw) "rw " rwRule (location)? : tactic
syntax (name := rwSeq) (priority := high) "rw " rwRuleSeq (location)? : tactic
syntax (name := erw) "erw " rwRule (location)? : tactic
syntax (name := erwSeq) (priority := high) "erw " rwRuleSeq (location)? : tactic
private def withCheapRefl (tac : Syntax) : MacroM Syntax :=
`(tactic| $tac; try (withReducible rfl))
@[macro rw]
def expandRw : Macro :=
fun stx => withCheapRefl (stx.setKind `Lean.Parser.Tactic.rewrite |>.setArg 0 (mkAtomFrom stx "rewrite"))
@[macro rwSeq]
def expandRwSeq : Macro :=
fun stx => withCheapRefl (stx.setKind `Lean.Parser.Tactic.rewriteSeq |>.setArg 0 (mkAtomFrom stx "rewrite"))
@[macro erw]
def expandERw : Macro :=
fun stx => withCheapRefl (stx.setKind `Lean.Parser.Tactic.erewrite |>.setArg 0 (mkAtomFrom stx "erewrite"))
@[macro erwSeq]
def expandERwSeq : Macro :=
fun stx => withCheapRefl (stx.setKind `Lean.Parser.Tactic.erewriteSeq |>.setArg 0 (mkAtomFrom stx "erewrite"))
syntax (name := injection) "injection " term (" with " (colGt (ident <|> "_"))+)? : tactic
syntax (name := «have») "have " haveDecl : tactic
syntax (name := «suffices») "suffices " sufficesDecl : tactic
syntax (name := «show») "show " term : tactic
syntax (name := «let») "let " letDecl : tactic
syntax (name := «let!») "let! " letDecl : tactic
syntax (name := letrec) withPosition(atomic(group("let " &"rec ")) letRecDecls) : tactic
syntax inductionAlt := "| " (ident <|> "_") (ident <|> "_")* " => " (hole <|> syntheticHole <|> tacticSeq)
syntax inductionAlts := "with " withPosition( (colGe inductionAlt)+)
syntax (name := induction) "induction " term,+ (" using " ident)? ("generalizing " ident+)? (inductionAlts)? : tactic
syntax casesTarget := atomic(ident " : ")? term
syntax (name := cases) "cases " casesTarget,+ (" using " ident)? (inductionAlts)? : tactic
syntax (name := existsIntro) "exists " term : tactic
/- We use a priority > default, to avoid ambiguity with the builtin `have` notation -/
macro (priority := high) "have" x:ident " := " p:term : tactic => `(have $x:ident : _ := $p)
syntax "repeat " tacticSeq : tactic
macro_rules
| `(tactic| repeat $seq) => `(tactic| first ($seq); repeat $seq | skip)
end Parser.Tactic
end Lean