forbid quering of chars

[AndreyMlashkin]

This PR forbids constructions like this:

JSONVar var;

var['f'] = "bar";

[CLAassistant]

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[github-actions[bot]]

Memory usage change @ aba948722fdf70996229109b15d97bfee0549aa6

Board	flash	%	RAM for global variables	%
arduino:avr:leonardo	0 - 0	0.0 - 0.0	0 - 0	0.0 - 0.0
arduino:avr:mega	0 - 0	0.0 - 0.0	0 - 0	0.0 - 0.0
arduino:avr:nano	0 - 0	0.0 - 0.0	0 - 0	0.0 - 0.0
arduino:avr:yun	0 - 0	0.0 - 0.0	0 - 0	0.0 - 0.0
arduino:mbed_edge:edge_control	0 - 0	0.0 - 0.0	0 - 0	0.0 - 0.0
arduino:mbed_nano:nano33ble	0 - 0	0.0 - 0.0	0 - 0	0.0 - 0.0
arduino:mbed_nano:nanorp2040connect	0 - 0	0.0 - 0.0	0 - 0	0.0 - 0.0
arduino:mbed_portenta:envie_m7:target_core=cm4	N/A	N/A	N/A	N/A
arduino:mbed_portenta:envie_m7	N/A	N/A	N/A	N/A
arduino:megaavr:nona4809	0 - 0	0.0 - 0.0	0 - 0	0.0 - 0.0
arduino:megaavr:uno2018	0 - 0	0.0 - 0.0	0 - 0	0.0 - 0.0
arduino:sam:arduino_due_x_dbg	0 - 0	0.0 - 0.0	N/A	N/A
arduino:samd:arduino_zero_edbg	0 - 0	0.0 - 0.0	0 - 0	0.0 - 0.0
arduino:samd:mkrzero	0 - 0	0.0 - 0.0	0 - 0	0.0 - 0.0
arduino:samd:nano_33_iot	0 - 0	0.0 - 0.0	0 - 0	0.0 - 0.0

Click for full report table

Board|`examples/JSONArray`
flash|%|`examples/JSONArray`
RAM for global variables|%|`examples/JSONKitchenSink`
flash|%|`examples/JSONKitchenSink`
RAM for global variables|%|`examples/JSONObject`
flash|%|`examples/JSONObject`
RAM for global variables|%|`examples/JSONValueExtractor`
flash|%|`examples/JSONValueExtractor`
RAM for global variables|% -|-|-|-|-|-|-|-|-|-|-|-|-|-|-|-|- `arduino:avr:leonardo`|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0 `arduino:avr:mega`|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0 `arduino:avr:nano`|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0 `arduino:avr:yun`|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0 `arduino:mbed_edge:edge_control`|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0 `arduino:mbed_nano:nano33ble`|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0 `arduino:mbed_nano:nanorp2040connect`|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0 `arduino:mbed_portenta:envie_m7:target_core=cm4`|N/A|N/A|N/A|N/A|N/A|N/A|N/A|N/A|N/A|N/A|N/A|N/A|N/A|N/A|N/A|N/A `arduino:mbed_portenta:envie_m7`|N/A|N/A|N/A|N/A|N/A|N/A|N/A|N/A|N/A|N/A|N/A|N/A|N/A|N/A|N/A|N/A `arduino:megaavr:nona4809`|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0 `arduino:megaavr:uno2018`|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0 `arduino:sam:arduino_due_x_dbg`|0|0.0|N/A|N/A|0|0.0|N/A|N/A|0|0.0|N/A|N/A|0|0.0|N/A|N/A `arduino:samd:arduino_zero_edbg`|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0 `arduino:samd:mkrzero`|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0 `arduino:samd:nano_33_iot`|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0|0|0.0

Click for full report CSV

``` Board,examples/JSONArray
flash,%,examples/JSONArray
RAM for global variables,%,examples/JSONKitchenSink
flash,%,examples/JSONKitchenSink
RAM for global variables,%,examples/JSONObject
flash,%,examples/JSONObject
RAM for global variables,%,examples/JSONValueExtractor
flash,%,examples/JSONValueExtractor
RAM for global variables,% arduino:avr:leonardo,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0 arduino:avr:mega,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0 arduino:avr:nano,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0 arduino:avr:yun,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0 arduino:mbed_edge:edge_control,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0 arduino:mbed_nano:nano33ble,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0 arduino:mbed_nano:nanorp2040connect,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0 arduino:mbed_portenta:envie_m7:target_core=cm4,N/A,N/A,N/A,N/A,N/A,N/A,N/A,N/A,N/A,N/A,N/A,N/A,N/A,N/A,N/A,N/A arduino:mbed_portenta:envie_m7,N/A,N/A,N/A,N/A,N/A,N/A,N/A,N/A,N/A,N/A,N/A,N/A,N/A,N/A,N/A,N/A arduino:megaavr:nona4809,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0 arduino:megaavr:uno2018,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0 arduino:sam:arduino_due_x_dbg,0,0.0,N/A,N/A,0,0.0,N/A,N/A,0,0.0,N/A,N/A,0,0.0,N/A,N/A arduino:samd:arduino_zero_edbg,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0 arduino:samd:mkrzero,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0 arduino:samd:nano_33_iot,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0 ```

[aentinger]

Hi @AndreyMlashkin :coffee: :wave:

Why do you feel such an amendment would be necessary?

[AndreyMlashkin]

Because I've got that issue in my code. Quering of 'a', 'b', 'c' was giving a crash

[aentinger]

It would be more interesting to know the source of the crash then just blanket delete that function ... any idea?

[AndreyMlashkin]

It would be more interesting to know the source of the crash then just blanket delete that function ... any idea?

Because it will interpret it as an array, not as object