Example sketches do not compile against current version of ArduinoJson

[Jefficus]

Compiling the demo8266.ino sketch fails due to conflicts as shown below. I was trying to compile against the latest ArduinoJson (16.18.4) but found that by reverting all the way back to 16.16.1, the compilation succeeded. Using the older version of the JSON library will probably be sufficient for my needs, but thought I should report this for the benefit of those who might need the newer version. Also, it might be worth documenting in the README which version of the ArduinoJson library has been verified.

/home/jeffs/Arduino/libraries/WebConfig/src/WebConfig.cpp: In member function 'void WebConfig::addDescription(String)':
/home/jeffs/Arduino/libraries/WebConfig/src/WebConfig.cpp:129:3: error: 'DeserializationError' was not declared in this scope
DeserializationError error;
^
/home/jeffs/Arduino/libraries/WebConfig/src/WebConfig.cpp:129:24: error: expected ';' before 'error'
DeserializationError error;
^
/home/jeffs/Arduino/libraries/WebConfig/src/WebConfig.cpp:132:3: error: 'DynamicJsonDocument' was not declared in this scope
DynamicJsonDocument doc(capacity);
^
/home/jeffs/Arduino/libraries/WebConfig/src/WebConfig.cpp:132:23: error: expected ';' before 'doc'
DynamicJsonDocument doc(capacity);
^
/home/jeffs/Arduino/libraries/WebConfig/src/WebConfig.cpp:134:3: error: 'error' was not declared in this scope
error = deserializeJson(doc,parameter);
^
/home/jeffs/Arduino/libraries/WebConfig/src/WebConfig.cpp:134:27: error: 'doc' was not declared in this scope
error = deserializeJson(doc,parameter);
^
/home/jeffs/Arduino/libraries/WebConfig/src/WebConfig.cpp:134:40: error: 'deserializeJson' was not declared in this scope
error = deserializeJson(doc,parameter);
^
/home/jeffs/Arduino/libraries/WebConfig/src/WebConfig.cpp:140:39: error: expected primary-expression before '>' token
JsonArray array = doc.as();
^
/home/jeffs/Arduino/libraries/WebConfig/src/WebConfig.cpp:140:41: error: expected primary-expression before ')' token
JsonArray array = doc.as();
^
/home/jeffs/Arduino/libraries/WebConfig/src/WebConfig.cpp:142:27: error: use of deleted function 'ArduinoJson::JsonObject::JsonObject(const ArduinoJson::JsonObject&)'
for (JsonObject obj : array) {
^
In file included from /home/jeffs/Arduino/libraries/ArduinoJson/ArduinoJson.hpp:12:0,
from /home/jeffs/Arduino/libraries/ArduinoJson/ArduinoJson.h:10,
from /home/jeffs/Arduino/libraries/WebConfig/src/WebConfig.cpp:27:
/home/jeffs/Arduino/libraries/ArduinoJson/ArduinoJson/JsonObject.hpp:39:7: note: 'ArduinoJson::JsonObject::JsonObject(const ArduinoJson::JsonObject&)' is implicitly deleted because the default definition would be ill-formed:
class JsonObject : public Internals::JsonPrintable,
^
In file included from /home/jeffs/Arduino/libraries/ArduinoJson/ArduinoJson/JsonArray.hpp:12:0,
from /home/jeffs/Arduino/libraries/ArduinoJson/ArduinoJson.hpp:11,
from /home/jeffs/Arduino/libraries/ArduinoJson/ArduinoJson.h:10,
from /home/jeffs/Arduino/libraries/WebConfig/src/WebConfig.cpp:27:
/home/jeffs/Arduino/libraries/ArduinoJson/ArduinoJson/Data/ReferenceType.hpp:31:3: error: 'ArduinoJson::Internals::ReferenceType::ReferenceType(const ArduinoJson::Internals::ReferenceType&)' is private
ReferenceType(const ReferenceType&);
^
In file included from /home/jeffs/Arduino/libraries/ArduinoJson/ArduinoJson.hpp:12:0,
from /home/jeffs/Arduino/libraries/ArduinoJson/ArduinoJson.h:10,
from /home/jeffs/Arduino/libraries/WebConfig/src/WebConfig.cpp:27:
/home/jeffs/Arduino/libraries/ArduinoJson/ArduinoJson/JsonObject.hpp:39:7: error: within this context
class JsonObject : public Internals::JsonPrintable,
^
/home/jeffs/Arduino/libraries/WebConfig/src/WebConfig.cpp:169:56: error: use of deleted function 'ArduinoJson::JsonArray::JsonArray(const ArduinoJson::JsonArray&)'
JsonArray opt = obj["options"].as();
^
In file included from /home/jeffs/Arduino/libraries/ArduinoJson/ArduinoJson.hpp:11:0,
from /home/jeffs/Arduino/libraries/ArduinoJson/ArduinoJson.h:10,
from /home/jeffs/Arduino/libraries/WebConfig/src/WebConfig.cpp:27:
/home/jeffs/Arduino/libraries/ArduinoJson/ArduinoJson/JsonArray.hpp:40:7: note: 'ArduinoJson::JsonArray::JsonArray(const ArduinoJson::JsonArray&)' is implicitly deleted because the default definition would be ill-formed:
class JsonArray : public Internals::JsonPrintable,
^
In file included from /home/jeffs/Arduino/libraries/ArduinoJson/ArduinoJson/JsonArray.hpp:12:0,
from /home/jeffs/Arduino/libraries/ArduinoJson/ArduinoJson.hpp:11,
from /home/jeffs/Arduino/libraries/ArduinoJson/ArduinoJson.h:10,
from /home/jeffs/Arduino/libraries/WebConfig/src/WebConfig.cpp:27:
/home/jeffs/Arduino/libraries/ArduinoJson/ArduinoJson/Data/ReferenceType.hpp:31:3: error: 'ArduinoJson::Internals::ReferenceType::ReferenceType(const ArduinoJson::Internals::ReferenceType&)' is private
ReferenceType(const ReferenceType&);
^
In file included from /home/jeffs/Arduino/libraries/ArduinoJson/ArduinoJson.hpp:11:0,
from /home/jeffs/Arduino/libraries/ArduinoJson/ArduinoJson.h:10,
from /home/jeffs/Arduino/libraries/WebConfig/src/WebConfig.cpp:27:
/home/jeffs/Arduino/libraries/ArduinoJson/ArduinoJson/JsonArray.hpp:40:7: error: within this context
class JsonArray : public Internals::JsonPrintable,
^
/home/jeffs/Arduino/libraries/WebConfig/src/WebConfig.cpp:171:31: error: use of deleted function 'ArduinoJson::JsonObject::JsonObject(const ArduinoJson::JsonObject&)'
for (JsonObject o : opt) {
^
/home/jeffs/Arduino/libraries/WebConfig/src/WebConfig.cpp: In member function 'String WebConfig::getResults()':
/home/jeffs/Arduino/libraries/WebConfig/src/WebConfig.cpp:493:3: error: 'StaticJsonDocument' was not declared in this scope
StaticJsonDocument<1000> doc;
^
/home/jeffs/Arduino/libraries/WebConfig/src/WebConfig.cpp:493:28: error: 'doc' was not declared in this scope
StaticJsonDocument<1000> doc;
^
/home/jeffs/Arduino/libraries/WebConfig/src/WebConfig.cpp:510:27: error: 'serializeJson' was not declared in this scope
serializeJson(doc,buffer);
^
/home/jeffs/Arduino/libraries/WebConfig/src/WebConfig.cpp: In member function 'void WebConfig::setValues(String)':
/home/jeffs/Arduino/libraries/WebConfig/src/WebConfig.cpp:519:3: error: 'DeserializationError' was not declared in this scope
DeserializationError error;
^
/home/jeffs/Arduino/libraries/WebConfig/src/WebConfig.cpp:519:24: error: expected ';' before 'error'
DeserializationError error;
^
/home/jeffs/Arduino/libraries/WebConfig/src/WebConfig.cpp:520:3: error: 'StaticJsonDocument' was not declared in this scope
StaticJsonDocument<1000> doc;
^
/home/jeffs/Arduino/libraries/WebConfig/src/WebConfig.cpp:520:28: error: 'doc' was not declared in this scope
StaticJsonDocument<1000> doc;
^
/home/jeffs/Arduino/libraries/WebConfig/src/WebConfig.cpp:521:3: error: 'error' was not declared in this scope
error = deserializeJson(doc, json);
^
/home/jeffs/Arduino/libraries/WebConfig/src/WebConfig.cpp:521:36: error: 'deserializeJson' was not declared in this scope
error = deserializeJson(doc, json);
^
exit status 1
Error compiling for board NodeMCU 1.0 (ESP-12E Module).

[KoffeinKaio]

6.18.5 compiles just fine for me
( you might have an error in your version strings, there is no (16.*)

[martibc16]

I got the same error, I fixed by using the version @KoffeinKaio mentions.
I don't now why but by default it picks version 5.13.4 which gives compilation errors.

Adding:

lib_deps = 
    https://github.com/bblanchon/ArduinoJson.git#6ea2815341582759ac566fc836ab575f6414563d

Solved the problem for me.