Idris2/libs/contrib/Language/JSON/String/Lexer.idr
Edwin Brady c88bf7af8d Fix import loading
This was taking too long, and adding too many things, because it was
going too deep in the name of having everything accessible at the REPL
and for the compiler. So, it's done a bit differently now, only chasing
everything on a "full" load (i.e., final load at the REPL)

This has some effects:
+ As systems get bigger, load time gets better (on my machine, checking
  Idris.Main now takes 52s from scratch, down from 76s)
+ You might find import errors that you didn't previously get, because
  things were being imported that shouldn't have been. The new way is
  correct!

An unfortunate effect is that sometimes you end up getting "undefined
name" errors even if you didn't explicitly use the name, because
sometimes a module uses a name from another module in a type, which then
gets exported, and eventually needs to be reduced. This mostly happens
because there is a compile time check that should be done which I
haven't implemented yet. That is, public export definitions should only
be allowed to use names that are also public export. I'll get to this
soon.
2020-05-27 15:49:03 +01:00

43 lines
853 B
Idris

module Language.JSON.String.Lexer
import Data.Nat
import Language.JSON.String.Tokens
import Text.Lexer
%default total
export
quo : Lexer
quo = is '"'
export
esc : Lexer -> Lexer
esc = escape '\\'
private
unicodeEscape : Lexer
unicodeEscape = esc $ is 'u' <+> count (exactly 4) hexDigit
private
simpleEscape : Lexer
simpleEscape = esc $ oneOf "\"\\/bfnrt"
private
legalChar : Lexer
legalChar = non (quo <|> is '\\' <|> control)
private
jsonStringTokenMap : TokenMap JSONStringToken
jsonStringTokenMap = toTokenMap $
[ (quo, JSTQuote)
, (unicodeEscape, JSTUnicodeEscape)
, (simpleEscape, JSTSimpleEscape)
, (legalChar, JSTChar)
]
export
lexString : String -> Maybe (List JSONStringToken)
lexString x = case lex jsonStringTokenMap x of
(toks, _, _, "") => Just $ map TokenData.tok toks
_ => Nothing