Error with non existing key

[AlejandroCastillejo]

• I am trying to read a value in a json file but I cannot be sure that the variable exists in the file.

• When I try to get the value of a non existing key it comes with an error and the program shuts down.
  I wonder if there if any way to check if a variable with this key exists in the file before reading it. So this way I could avoid he error.

Thank you for your help

[t-b]

@AlejandroCastillejo The contains method should do the trick, see https://nlohmann.github.io/json/classnlohmann_1_1basic__json_a9286acdc0578fc66e9346323e69fc0e3.html#a9286acdc0578fc66e9346323e69fc0e3.

[AlejandroCastillejo]

Thank you for your response.
Now there is another Issue since I changed to the last version of the single include file.
When I try to compile, there are some error messages like this:
error: redefinition of ‘class nlohmann::json_pointer’
class json_pointer

Before I was using version 3.1.2. I updated it because this previous version does not include the 'contains' method.

Thanks again for your help.

[nlohmann]

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• Please describe the steps to reproduce the issue. Can you provide a small but working code example?

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