Class: Muskox::Pure::Lexer

Inherits:
StringScanner
  • Object
show all
Defined in:
lib/muskox/json_lexer.rb

Constant Summary collapse

STRING = 
/" ((?:[^\x0-\x1f"\\] |
     # escaped special characters:
    \\["\\\/bfnrt] |
    \\u[0-9a-fA-F]{4} |
     # match all but escaped special characters:
    \\[\x20-\x21\x23-\x2e\x30-\x5b\x5d-\x61\x63-\x65\x67-\x6d\x6f-\x71\x73\x75-\xff])*)
"/nx
INTEGER = 
/(-?0|-?[1-9]\d*)/
FLOAT = 
/(-?
(?:0|[1-9]\d*)
(?:
  \.\d+(?i:e[+-]?\d+) |
  \.\d+ |
  (?i:e[+-]?\d+)
)
)/x
NAN = 
/NaN/
INFINITY = 
/Infinity/
MINUS_INFINITY = 
/-Infinity/
OBJECT_OPEN = 
/\{/
OBJECT_CLOSE = 
/\}/
ARRAY_OPEN = 
/\[/
ARRAY_CLOSE = 
/\]/
PAIR_DELIMITER = 
/:/
COLLECTION_DELIMITER = 
/,/
TRUE = 
/true/
FALSE = 
/false/
NULL = 
/null/
IGNORE = 
%r(
  (?:
   //[^\n\r]*[\n\r]| # line comments
   /\*               # c-style comments
   (?:
    [^*/]|        # normal chars
    /[^*]|        # slashes that do not start a nested comment
    \*[^/]|       # asterisks that do not end this comment
    /(?=\*/)      # single slash before this comment's end
   )*
     \*/               # the End of this comment
     |[ \t\r\n]+       # whitespaces: space, horicontal tab, lf, cr
  )+
)mx
UNPARSED = 
Object.new

Instance Method Summary collapse

Constructor Details

#initialize(source, opts = {}) ⇒ Lexer

Creates a new JSON::Pure::Parser instance for the string source.

It will be configured by the opts hash. opts can have the following keys:

  • max_nesting: The maximum depth of nesting allowed in the parsed data structures. Disable depth checking with :max_nesting => false|nil|0, it defaults to 100.

  • allow_nan: If set to true, allow NaN, Infinity and -Infinity in defiance of RFC 4627 to be parsed by the Parser. This option defaults to false.

  • symbolize_names: If set to true, returns symbols for the names (keys) in a JSON object. Otherwise strings are returned, which is also the default.

  • quirks_mode: Enables quirks_mode for parser, that is for example parsing single JSON values instead of documents is possible.



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# File 'lib/muskox/json_lexer.rb', line 69

def initialize(source, opts = {})
  opts ||= {}
  unless @quirks_mode = opts[:quirks_mode]
    source = convert_encoding source
  end
  super source
  if !opts.key?(:max_nesting) # defaults to 100
    @max_nesting = 100
  elsif opts[:max_nesting]
    @max_nesting = opts[:max_nesting]
  else
    @max_nesting = 0
  end
  @allow_nan = !!opts[:allow_nan]
  @symbolize_names = !!opts[:symbolize_names]
  @match_string = opts[:match_string]
end

Instance Method Details

#lex(&block) ⇒ Object

Parses the current JSON string source and returns the complete data structure as a result.



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# File 'lib/muskox/json_lexer.rb', line 100

def lex &block
  @callback = block
  reset
  if @quirks_mode
    while !eos? && skip(IGNORE)
    end
    if eos?
      raise ParserError, "source did not contain any JSON!"
    else
      obj = lex_value
      obj == UNPARSED and raise ParserError, "source did not contain any JSON!"
    end
  else
    until eos?
      case
      when scan(OBJECT_OPEN)
#              obj and raise ParserError, "source '#{peek(20)}' not in JSON!"
        @current_nesting = 1
        lex_object
      when scan(ARRAY_OPEN)
#              obj and raise ParserError, "source '#{peek(20)}' not in JSON!"
        @current_nesting = 1
        lex_array
      when skip(IGNORE)
        ;
      else
        raise ParserError, "source '#{peek(20)}' not in JSON!"
      end
    end
#          obj or raise ParserError, "source did not contain any JSON!"
  end
#        obj
end

#quirks_mode? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/muskox/json_lexer.rb', line 89

def quirks_mode?
  !!@quirks_mode
end

#reset ⇒ Object 



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# File 'lib/muskox/json_lexer.rb', line 93

def reset
  super
  @current_nesting = 0
end