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* Proper error handling when parsed number exceeds uint64

details:
  Returns an "errNonPortableInt" error

* need legacy flag for unit tests

* lazy numeric token parser

why:
  Numeric data may have a custom format. In particular,numeric data may be
  Uint256 which is not a JSON standard and might lead to an overflow.

details:
  Numeric values are assigned a preliminary token type tkNumeric without
  being fully parsed. This can be used to insert a custom parser.
  Otherwise the value is parsed implicitly when querying/fetching the
  token type.

  + tok:     replaced by getter tok() resolving lazy stuff (if necessary)
  + tokKind: current type without auto-resolving

  This lazy scheme could be extended to other custom types as long as
  the first token letter determines the custom type.

* activate lazy parsing in reader

howto:
  + no code change if a custom reader refers to an existing reader
    type FancyInt = distinct int
    proc readValue(reader: var JsonReader, value: var FancyInt) =
      value = reader.readValue(int).FancyInt

  + bespoke reader for cusom parsing
    type FancyUint = distinct uint
    proc readValue(reader: var JsonReader, value: var FancyUint) =
      if reader.lexer.lazyTok == tkNumeric:
        var accu: FancyUint
        reader.lexer.customIntValueIt:
          accu = accu * 10 + it.u256
        value = accu
      elif reader.lexer.tok == tkString:
        value = reader.lexer.strVal.parseUint.FancyUint
        ...
      reader.lexer.next

  + full code explanation at json_serialisation/reader.readValue()

* Add lazy parsing for customised string objects

why:
  This allows parsing large or specialised strings without storing it
  in the lexer state descriptor.

details:
  Similar logic applies as for the cusomised number parser. For mostly
  all practical cases, a DSL template is available serving as wrapper
  around the character/byte item processor code.

* fix typo in unit test

2022-05-05 17:33:40 +01:00

.github/workflows

CI: test with multiple Nim versions (#35 )

2022-01-06 20:10:03 +01:00

json_serialization

Lazy JSON parser (#42 )

2022-05-05 17:33:40 +01:00

tests

Lazy JSON parser (#42 )

2022-05-05 17:33:40 +01:00

.appveyor.yml

revert, just in case some action-at-a-distance thing is causing Unhandled exception: assignment to discriminant changes object branch; compile with -d:nimOldCaseObjects for a transition period [FieldError]