{-# LANGUAGE NoImplicitPrelude #-}-- |-- Module: Data.Aeson.Parser-- Copyright: (c) 2012-2016 Bryan O'Sullivan-- (c) 2011 MailRank, Inc.-- License: BSD3-- Maintainer: Bryan O'Sullivan <bos@serpentine.com>-- Stability: experimental-- Portability: portable---- Efficiently and correctly parse a JSON string. The string must be-- encoded as UTF-8.---- It can be useful to think of parsing as occurring in two phases:---- * Identification of the textual boundaries of a JSON value. This-- is always strict, so that an invalid JSON document can be-- rejected as soon as possible.---- * Conversion of a JSON value to a Haskell value. This may be-- either immediate (strict) or deferred (lazy); see below for-- details.---- The question of whether to choose a lazy or strict parser is-- subtle, but it can have significant performance implications,-- resulting in changes in CPU use and memory footprint of 30% to 50%,-- or occasionally more. Measure the performance of your application-- with each!moduleData.Aeson.Parser(-- * Lazy parsers-- $lazyjson ,value ,jstring ,scientific -- ** Handling objects with duplicate keys,jsonWith ,jsonLast ,jsonAccum ,jsonNoDup -- * Strict parsers-- $strict,json' ,value' -- ** Handling objects with duplicate keys,jsonWith' ,jsonLast' ,jsonAccum' ,jsonNoDup' -- * Decoding without FromJSON instances,decodeWith ,decodeStrictWith ,eitherDecodeWith ,eitherDecodeStrictWith )whereimportData.Aeson.Parser.Internal -- $lazy---- The 'json' and 'value' parsers decouple identification from-- conversion. Identification occurs immediately (so that an invalid-- JSON document can be rejected as early as possible), but conversion-- to a Haskell value is deferred until that value is needed.---- This decoupling can be time-efficient if only a smallish subset of-- elements in a JSON value need to be inspected, since the cost of-- conversion is zero for uninspected elements. The trade off is an-- increase in memory usage, due to allocation of thunks for values-- that have not yet been converted.-- $strict---- The 'json'' and 'value'' parsers combine identification with-- conversion. They consume more CPU cycles up front, but have a-- smaller memory footprint.