json: slow as hell

[scriptum]

I have a very BIG issue with loading ~2 MB json data. It looks like parsing time grows exponentially while increasing data size.
Here is python sample:

import json
d = {}
for i in range(1, 200000):
  d[str(i)] = i
json.loads(json.dumps(d)) # 0.55 sec

Now guess Nim's time:

import json
let jobj = newJObject()
for i in 1..<200000:
  jobj.add($i, newJInt(i))
let jobj_parsed = parseJSon($jobj)

[refi64]

"Now guess Nim's time" leads back to this page. Does it take 3809 seconds or something?

[scriptum]

This is a hover-spoiler 😄

[Araq]

Give us the test-json somehow.

[def-]

@Araq It's created by the test program.

[scriptum]

@Araq this is simplified test that exactly reproduces my case. I have a many key-value pairs in json format, approximately 2 Megabytes.

You may also try this as test input:
(echo "{"; sed 's/.*/"&":null,/' /usr/share/dict/words; echo "}") > test.json

[refi64]

I had to download another web browser just to see it (on Android ATM).

[scriptum]

@kirbyfan64 I'm sorry this was simplest way to create spoiler on GitHub

[def-]

The problem is that a JObject's fields are a seq of key, val pairs. When you want to insert a new key it is checked for equivalence to each existing key. If I remove that one check it finishes in 0.2 seconds on my computer. I'll try to use a Table instead.

[scriptum]

@def- 0.2 - sounds good!

[def-]

@scriptum Take a look at #3810 please, faster than python for me.