# # This example demonstrates an experimental feature: Text reconstruction # The Reconstructor takes a parse tree (already filtered from punctuation, of course), # and reconstructs it into correct text, that can be parsed correctly. # It can be useful for creating "hooks" to alter data before handing it to other parsers. You can also use it to generate samples from scratch. # import json from lark import Lark from lark.reconstruct import Reconstructor from .json_parser import json_grammar test_json = ''' { "empty_object" : {}, "empty_array" : [], "booleans" : { "YES" : true, "NO" : false }, "numbers" : [ 0, 1, -2, 3.3, 4.4e5, 6.6e-7 ], "strings" : [ "This", [ "And" , "That", "And a \\"b" ] ], "nothing" : null } ''' def test_scanless(): json_parser = Lark(json_grammar, lexer=None) tree = json_parser.parse(test_json) # print ('@@', tree.pretty()) # for x in tree.find_data('true'): # x.data = 'false' # # x.children[0].value = '"HAHA"' new_json = Reconstructor(json_parser).reconstruct(tree) print (new_json) print (json.loads(new_json) == json.loads(test_json)) def test_lalr(): json_parser = Lark(json_grammar, parser='lalr') tree = json_parser.parse(test_json) new_json = Reconstructor(json_parser).reconstruct(tree) print (new_json) print (json.loads(new_json) == json.loads(test_json)) test_scanless() test_lalr()