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hydra-0.12.0: src/main/haskell/Hydra/Sources/Kernel/Terms/Grammars.hs

{-# LANGUAGE OverloadedStrings #-}

module Hydra.Sources.Kernel.Terms.Grammars where

-- Standard imports for term-level kernel modules
import Hydra.Kernel
import Hydra.Sources.Libraries
import qualified Hydra.Dsl.Accessors     as Accessors
import qualified Hydra.Dsl.Ast           as Ast
import qualified Hydra.Dsl.Coders        as Coders
import qualified Hydra.Dsl.Compute       as Compute
import qualified Hydra.Dsl.Core          as Core
import qualified Hydra.Dsl.Grammar       as Grammar
import qualified Hydra.Dsl.Graph         as Graph
import qualified Hydra.Dsl.Json          as Json
import qualified Hydra.Dsl.Lib.Chars     as Chars
import qualified Hydra.Dsl.Lib.Equality  as Equality
import qualified Hydra.Dsl.Lib.Flows     as Flows
import qualified Hydra.Dsl.Lib.Lists     as Lists
import qualified Hydra.Dsl.Lib.Literals  as Literals
import qualified Hydra.Dsl.Lib.Logic     as Logic
import qualified Hydra.Dsl.Lib.Maps      as Maps
import qualified Hydra.Dsl.Lib.Math      as Math
import qualified Hydra.Dsl.Lib.Optionals as Optionals
import           Hydra.Dsl.Phantoms      as Phantoms
import qualified Hydra.Dsl.Lib.Sets      as Sets
import           Hydra.Dsl.Lib.Strings   as Strings
import qualified Hydra.Dsl.Mantle        as Mantle
import qualified Hydra.Dsl.Module        as Module
import qualified Hydra.Dsl.TTerms        as TTerms
import qualified Hydra.Dsl.TTypes        as TTypes
import qualified Hydra.Dsl.Terms         as Terms
import qualified Hydra.Dsl.Topology      as Topology
import qualified Hydra.Dsl.Types         as Types
import qualified Hydra.Dsl.Typing        as Typing
import           Hydra.Sources.Kernel.Types.All
import           Prelude hiding ((++))
import qualified Data.Int                as I
import qualified Data.List               as L
import qualified Data.Map                as M
import qualified Data.Set                as S
import qualified Data.Maybe              as Y

import qualified Hydra.Sources.Kernel.Terms.Annotations as Annotations
import qualified Hydra.Sources.Kernel.Terms.Constants as Constants
import qualified Hydra.Sources.Kernel.Terms.Formatting as Formatting
import qualified Hydra.Sources.Kernel.Terms.Names as Names

import Hydra.Grammar as G


module_ :: Module
module_ = Module (Namespace "hydra.grammars") elements
    [Annotations.module_, Formatting.module_, Names.module_]
    kernelTypesModules $
    Just ("A utility for converting a BNF grammar to a Hydra module.")
  where
   elements = [
     el childNameDef,
     el findNamesDef,
     el grammarToModuleDef,
     el isComplexDef,
     el isNontrivialDef,
     el makeElementsDef,
     el rawNameDef,
     el simplifyDef,
     el toNameDef,
     el wrapTypeDef]

define :: String -> TTerm a -> TBinding a
define = definitionInModule module_

childNameDef :: TBinding (String -> String -> String)
childNameDef = define "childName" $
  doc "Generate child name" $
  lambda "lname" $ lambda "n" $
    Strings.cat $ list [var "lname", string "_", ref Formatting.capitalizeDef @@ var "n"]

findNamesDef :: TBinding ([G.Pattern] -> [String])
findNamesDef = define "findNames" $
  doc "Find unique names for patterns" $
  lambda "pats" $ lets [
    "nextName">: lambda "acc" $ lambda "pat" $ lets [
      "names">: first $ var "acc",
      "nameMap">: second $ var "acc",
      "rn">: ref rawNameDef @@ var "pat",
      "nameAndIndex">: Optionals.maybe
        (pair (var "rn") (int32 1))
        (lambda "i" $ pair (Strings.cat2 (var "rn") (Literals.showInt32 $ Math.add (var "i") (int32 1))) (Math.add (var "i") (int32 1)))
        (Maps.lookup (var "rn") (var "nameMap")),
      "nn">: first $ var "nameAndIndex",
      "ni">: second $ var "nameAndIndex"]
      $ pair
        (Lists.cons (var "nn") (var "names"))
        (Maps.insert (var "rn") (var "ni") (var "nameMap"))]
    $ Lists.reverse $ first $ Lists.foldl (var "nextName") (pair (list []) Maps.empty) (var "pats")

grammarToModuleDef :: TBinding (Namespace -> G.Grammar -> Maybe String -> Module)
grammarToModuleDef = define "grammarToModule" $
  doc "Convert a BNF grammar to a Hydra module" $
  lambda "ns" $ lambda "grammar" $ lambda "desc" $ lets [
    "prodPairs">: Lists.map
      (lambda "prod" $ pair
        (Grammar.unSymbol $ Grammar.productionSymbol $ var "prod")
        (Grammar.productionPattern $ var "prod"))
      (Grammar.unGrammar $ var "grammar"),
    "capitalizedNames">: Lists.map (lambda "pair" $ ref Formatting.capitalizeDef @@ (first $ var "pair")) (var "prodPairs"),
    "patterns">: Lists.map (lambda "pair" $ second $ var "pair") (var "prodPairs"),
    "elementPairs">: Lists.concat $ Lists.zipWith
      (ref makeElementsDef @@ false @@ var "ns")
      (var "capitalizedNames")
      (var "patterns"),
    "elements">: Lists.map
      (lambda "pair" $ lets [
        "lname">: first $ var "pair",
        "typ">: ref wrapTypeDef @@ (second $ var "pair")]
        $ ref Annotations.typeElementDef @@ (ref toNameDef @@ var "ns" @@ var "lname") @@ var "typ")
      (var "elementPairs")]
    $ Module.module_ (var "ns") (var "elements") (list []) (list []) (var "desc")

isComplexDef :: TBinding (G.Pattern -> Bool)
isComplexDef = define "isComplex" $
  doc "Check if pattern is complex" $
  lambda "pat" $ match G._Pattern (Just false) [
    _Pattern_labeled>>: lambda "lp" $ ref isComplexDef @@ (Grammar.labeledPatternPattern $ var "lp"),
    _Pattern_sequence>>: lambda "pats" $ ref isNontrivialDef @@ true @@ var "pats",
    _Pattern_alternatives>>: lambda "pats" $ ref isNontrivialDef @@ false @@ var "pats"]
  @@ var "pat"

isNontrivialDef :: TBinding (Bool -> [G.Pattern] -> Bool)
isNontrivialDef = define "isNontrivial" $
  doc "Check if patterns are nontrivial" $
  lambda "isRecord" $ lambda "pats" $ lets [
    "minPats">: ref simplifyDef @@ var "isRecord" @@ var "pats"]
    $ Logic.ifElse (Equality.equal (Lists.length $ var "minPats") (int32 1))
        (match G._Pattern (Just false) [
          _Pattern_labeled>>: constant true] @@ Lists.head (var "minPats"))
        true

makeElementsDef :: TBinding (Bool -> Namespace -> String -> G.Pattern -> [(String, Type)])
makeElementsDef = define "makeElements" $
  doc "Create elements from pattern" $
  lambda "omitTrivial" $ lambda "ns" $ lambda "lname" $ lambda "pat" $ lets [
    "trivial">: Logic.ifElse (var "omitTrivial") (list []) (list [pair (var "lname") TTypes.unit]),

    "forRecordOrUnion">: lambda "isRecord" $ lambda "construct" $ lambda "pats" $ lets [
      "minPats">: ref simplifyDef @@ var "isRecord" @@ var "pats",
      "fieldNames">: ref findNamesDef @@ var "minPats",
      "toField">: lambda "n" $ lambda "p" $ var "descend" @@ var "n" @@
        (lambda "pairs" $ pair (Core.fieldType (Core.name $ var "n") (second $ Lists.head $ var "pairs")) (Lists.tail $ var "pairs")) @@
        var "p",
      "fieldPairs">: Lists.zipWith (var "toField") (var "fieldNames") (var "minPats"),
      "fields">: Lists.map (unaryFunction first) (var "fieldPairs"),
      "els">: Lists.concat $ Lists.map (unaryFunction second) (var "fieldPairs")]
      $ Logic.ifElse (ref isNontrivialDef @@ var "isRecord" @@ var "pats")
          (Lists.cons (pair (var "lname") (var "construct" @@ var "fields")) (var "els"))
          (var "forPat" @@ (Lists.head $ var "minPats")),

    "mod">: lambda "n" $ lambda "f" $ lambda "p" $ var "descend" @@ var "n" @@
      (lambda "pairs" $ Lists.cons (pair (var "lname") (var "f" @@ (second $ Lists.head $ var "pairs"))) (Lists.tail $ var "pairs")) @@
      var "p",

    "descend">: lambda "n" $ lambda "f" $ lambda "p" $ lets [
      "cpairs">: ref makeElementsDef @@ false @@ var "ns" @@ (ref childNameDef @@ var "lname" @@ var "n") @@ var "p"]
      $ var "f" @@ Logic.ifElse (ref isComplexDef @@ var "p")
          (Lists.cons (pair (var "lname") (Core.typeVariable $ ref toNameDef @@ var "ns" @@ (first $ Lists.head $ var "cpairs"))) (var "cpairs"))
          (Logic.ifElse (Lists.null $ var "cpairs")
            (list [pair (var "lname") TTypes.unit])
            (Lists.cons (pair (var "lname") (second $ Lists.head $ var "cpairs")) (Lists.tail $ var "cpairs"))),

    "forPat">: lambda "pat" $ match G._Pattern Nothing [
      _Pattern_alternatives>>: lambda "pats" $ var "forRecordOrUnion" @@ false @@
        (lambda "fields" $ Core.typeUnion $ Core.rowType (ref Constants.placeholderNameDef) (var "fields")) @@ var "pats",
      _Pattern_constant>>: constant $ var "trivial",
      _Pattern_ignored>>: constant $ list [],
      _Pattern_labeled>>: lambda "lp" $ var "forPat" @@ Grammar.labeledPatternPattern (var "lp"),
      _Pattern_nil>>: constant $ var "trivial",
      _Pattern_nonterminal>>: lambda "s" $ list [pair (var "lname") $ Core.typeVariable $
        ref toNameDef @@ var "ns" @@ Grammar.unSymbol (var "s")],
      _Pattern_option>>: lambda "p" $ var "mod" @@ string "Option" @@ (unaryFunction TTypes.optional) @@ var "p",
      _Pattern_plus>>: lambda "p" $ var "mod" @@ string "Elmt" @@ (unaryFunction TTypes.list) @@ var "p",
      _Pattern_regex>>: constant $ list [pair (var "lname") TTypes.string],
      _Pattern_sequence>>: lambda "pats" $ var "forRecordOrUnion" @@ true @@
        (lambda "fields" $ Core.typeRecord $ Core.rowType (ref Constants.placeholderNameDef) (var "fields")) @@ var "pats",
      _Pattern_star>>: lambda "p" $ var "mod" @@ string "Elmt" @@ (unaryFunction TTypes.list) @@ var "p"]
    @@ var "pat"]
    $ var "forPat" @@ var "pat"

rawNameDef :: TBinding (G.Pattern -> String)
rawNameDef = define "rawName" $
  doc "Get raw name from pattern" $
  lambda "pat" $ match G._Pattern Nothing [
    _Pattern_alternatives>>: constant $ string "alts",
    _Pattern_constant>>: lambda "c" $ ref Formatting.capitalizeDef @@ (ref Formatting.withCharacterAliasesDef @@ (Grammar.unConstant $ var "c")),
    _Pattern_ignored>>: constant $ string "ignored",
    _Pattern_labeled>>: lambda "lp" $ Grammar.unLabel $ Grammar.labeledPatternLabel $ var "lp",
    _Pattern_nil>>: constant $ string "none",
    _Pattern_nonterminal>>: lambda "s" $ ref Formatting.capitalizeDef @@ (Grammar.unSymbol $ var "s"),
    _Pattern_option>>: lambda "p" $ ref Formatting.capitalizeDef @@ (ref rawNameDef @@ var "p"),
    _Pattern_plus>>: lambda "p" $ Strings.cat2 (string "listOf") (ref Formatting.capitalizeDef @@ (ref rawNameDef @@ var "p")),
    _Pattern_regex>>: constant $ string "regex",
    _Pattern_sequence>>: constant $ string "sequence",
    _Pattern_star>>: lambda "p" $ Strings.cat2 (string "listOf") (ref Formatting.capitalizeDef @@ (ref rawNameDef @@ var "p"))]
  @@ var "pat"

simplifyDef :: TBinding (Bool -> [G.Pattern] -> [G.Pattern])
simplifyDef = define "simplify" $
  doc "Remove trivial patterns from records" $
  lambda "isRecord" $ lambda "pats" $ lets [
    "isConstant">: lambda "p" $ match G._Pattern (Just false) [
      G._Pattern_constant>>: constant true] @@ var "p"]
    $ Logic.ifElse (var "isRecord")
        (Lists.filter (lambda "p" $ Logic.not $ var "isConstant" @@ var "p") (var "pats"))
        (var "pats")

toNameDef :: TBinding (Namespace -> String -> Name)
toNameDef = define "toName" $
  doc "Convert local name to qualified name" $
  lambda "ns" $ lambda "local" $
    ref Names.unqualifyNameDef @@ (Module.qualifiedName (just $ var "ns") (var "local"))

wrapTypeDef :: TBinding (Type -> Type)
wrapTypeDef = define "wrapType" $
  doc "Wrap a type in a placeholder name, unless it is already a wrapper, record, or union type" $
  lambda "t" $ cases _Type (var "t") (Just $ Core.typeWrap $ Core.wrappedType (Core.nameLift placeholderName) $ var "t") [
    _Type_record>>: constant $ var "t",
    _Type_union>>: constant $ var "t",
    _Type_wrap>>: constant $ var "t"]