I've got a long string. This string contains a list, like such example
'[{"ex1": 0, "ex2":1}, {"ex3": 2, "ex4":3}]'
I can use json5.loads and then get the first element by using [0] on the list, but json5.loads takes a long time for longer strings. Is there a way to get just the first element without loading the entire list? (in this example it would be {"ex1": 0, "ex2":1}. Splitting by commas doesn't work for me since there are commas contained in dictionaries in the list. Thanks.
Does your string work with ast.literal_eval()? If it does, you could do
obj = ast.literal_eval(s)
# obj[0] gives the first dict
If not, you could loop through the string character-by-character and yield any substring when the number of open-brackets are equal to the number of close-brackets.
def get_top_level_dict_str(s):
open_br = 0
close_br = 0
open_index = 0
for i, c in enumerate(s):
if c == '{':
if open_br == 0: open_index = i
open_br += 1
elif c == '}':
close_br += 1
if open_br > 0 and open_br == close_br:
yield s[open_index:i+1]
open_br = close_br = 0
If you want to parse the resulting substrings to objects, you could use json5 like you already do, which is probably faster on the smaller string, or use ast.literal_eval()
x = get_top_level_dict_str(s)
# next(x) gives the substring
# then use json5 or ast.literal_eval()