hnix/Nix/Pretty.hs
2014-08-13 19:33:19 +02:00

80 lines
3.1 KiB
Haskell

module Nix.Pretty where
import Data.Map (toList)
import Data.Text (Text, unpack)
import Nix.Types
import Text.PrettyPrint.ANSI.Leijen
prettyBind :: Binding NExpr -> Doc
prettyBind (NamedVar n v) = prettyNix n <+> equals <+> prettyNix v <> semi
prettyBind (Inherit ns) = text "inherit" <+> fillSep (map prettyNix ns) <> semi
prettyBind (ScopedInherit s ns) = text "inherit" <+> parens (prettyNix s) <+> fillSep (map prettyNix ns) <> semi
prettyFormals :: Formals NExpr -> Doc
prettyFormals (FormalName n) = text $ unpack n
prettyFormals (FormalSet s) = prettyParamSet s
prettyFormals (FormalLeftAt n s) = text (unpack n) <> text "@" <> prettyParamSet s
prettyFormals (FormalRightAt s n) = prettyParamSet s <> text "@" <> text (unpack n)
prettyParamSet :: FormalParamSet NExpr -> Doc
prettyParamSet (FormalParamSet args) = lbrace <+> hcat (map prettySetArg $ toList args) <+> rbrace
prettySetArg :: (Text, Maybe NExpr) -> Doc
prettySetArg (n, Nothing) = text (unpack n)
prettySetArg (n, Just v) = text (unpack n) <+> text "?" <+> prettyNix v
infixOper :: NExpr -> String -> NExpr -> Doc
infixOper l op r = prettyNix l <+> text op <+> prettyNix r
prettyOper :: NOperF NExpr -> Doc
prettyOper (NNot r) = text "!" <> prettyNix r
prettyOper (NNeg r) = text "-" <> prettyNix r
prettyOper (NEq r1 r2) = infixOper r1 "==" r2
prettyOper (NNEq r1 r2) = infixOper r1 "!=" r2
prettyOper (NLt r1 r2) = infixOper r1 "<" r2
prettyOper (NLte r1 r2) = infixOper r1 "<=" r2
prettyOper (NGt r1 r2) = infixOper r1 ">" r2
prettyOper (NGte r1 r2) = infixOper r1 ">=" r2
prettyOper (NAnd r1 r2) = infixOper r1 "&&" r2
prettyOper (NOr r1 r2) = infixOper r1 "||" r2
prettyOper (NImpl r1 r2) = infixOper r1 ">" r2
prettyOper (NUpdate r1 r2) = infixOper r1 "//" r2
prettyOper (NHasAttr r1 r2) = infixOper r1 "?" r2
prettyOper (NAttr r1 r2) = prettyNix r1 <> text "." <> prettyNix r2
prettyOper (NPlus r1 r2) = infixOper r1 "+" r2
prettyOper (NMinus r1 r2) = infixOper r1 "-" r2
prettyOper (NMult r1 r2) = infixOper r1 "*" r2
prettyOper (NDiv r1 r2) = infixOper r1 "/" r2
prettyOper (NConcat r1 r2) = infixOper r1 "++" r2
prettyAtom :: NAtom -> Doc
prettyAtom (NStr s) = dquotes $ text $ unpack s
prettyAtom atom = text $ unpack $ atomText atom
prettyNix :: NExpr -> Doc
prettyNix (Fix expr) = go expr where
go (NConstant atom) = prettyAtom atom
go (NOper oper) = prettyOper oper
go (NList xs) = lbracket <+> fillSep (map prettyNix xs) <+> rbracket
go (NArgs fs) = prettyFormals fs
go (NSet rec xs) =
(case rec of Rec -> "rec"; NonRec -> empty)
<+> lbrace <+> vcat (map prettyBind xs) <+> rbrace
go (NLet _binds _body) = text "let"
go (NIf cond trueBody falseBody) =
(text "if" <+> prettyNix cond)
<$$> (text "then" <+> prettyNix trueBody)
<$$> (text "else" <+> prettyNix falseBody)
go (NWith scope body) = text "with" <+> prettyNix scope <> semi <+> prettyNix body
go (NAssert cond body) = text "assert" <+> prettyNix cond <> semi <+> prettyNix body
go (NVar e) = prettyNix e
go (NApp fun arg) = prettyNix fun <+> parens (prettyNix arg)
go (NAbs args body) = (prettyNix args <> colon) <$$> prettyNix body