"""Strict JSON decoding without silent key loss or non-JSON numeric values."""
import json
import math


def _object(pairs):
    result = {}
    for key, value in pairs:
        if key in result:
            raise ValueError(f"Duplicate JSON key: {key!r}.")
        result[key] = value
    return result


def _constant(value):
    raise ValueError(f"{value} is not a valid JSON value.")


def _float(value):
    number = float(value)
    if not math.isfinite(number):
        raise ValueError("JSON number exceeds the supported finite range.")
    return number


def strict_json_loads(text):
    return json.loads(text, object_pairs_hook=_object, parse_constant=_constant, parse_float=_float)